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Gas injection volume is the key parameter of air drilling with raise boring machine, and the determination of the minimum gas injection volume is one of the key technologies to improve the drilling speed and shorten the drilling period. Based on the characteristics of raise boring technology, the construction technique of raise boring with air as circulating medium is studied, and the double-channel structural characteristics of direct circulation system are discussed. On the basis of summarizing and analyzing the principle and characteristics of the calculation methods, the minimum gas injection volume required for rock carrying in the engineering of air drilling with raise boring machine is calculated by using the minimum velocity method. The research results provide a basis for the design of drilling parameters and are of great significance for expanding the application range of raise boring method and realizing the safe and rapid construction of shaft.

The EN ISO 52016-1 standard presents a new simplified dynamic calculation procedure, whose aim is to provide an accurate energy performance assessment without excessively increasing the number of data required. The Italian National Annex to EN ISO 52016-1, currently under development, provides some improvements to the hourly calculation method; despite many works can be found in literature on the hourly model of EN ISO 52016-1, the National Annexes application has not been sufficiently analysed yet. The aim of the present work is to assess the main improvements introduced by the Italian National Annex and to compare the main results, in terms of energy need for space heating and cooling. To this purpose, an existing building representative of the Italian office building stock in Northern Italy was selected as a case study. The energy simulations were carried out considering both continuous and reduced operation of the HVAC systems. The options specified in the Italian National Annex were firstly applied one by one, and then all together. The variation of the energy need compared to the international base procedure is finally quantified. For the premises and the scope above discussed, the present work is intended to enhance the standardisation activity towards the adoption of more accurate and trustable calculation methods of the building energy performance.

The article provides an analysis of methods for calculating electricity losses. The conditions for the application of methods for calculating electricity losses are determined, and structural separated losses in electrical networks are shown. A modern classification of losses is presented, and methods for calculating technological losses of electricity are considered.

The external reinforcement system based on carbon fiber has been used for decades to strengthen reinforced concrete elements. At the same time, it is impossible not to recognize that the existing calculation methods are largely based on empirical dependencies obtained from experimental studies. One of these issues is related to the application of the methodology for materials of heterogeneous origin-tapes and laminates. In general, the possibility of applying the calculation methods accepted in the norms for laminates of generally accepted thicknesses up to 1.6 mm is determined. The question related to the possibility of using laminates of greater thickness is not sufficiently studied. This article deals with the calculation of the reinforcement of the normal cross sections of the bent reinforced concrete elements with the reinforcement of laminates with a thickness of 5 mm.

Fully ceramic micro-encapsulated (FCM) fuel is a kind of fuel that employs tri-structural isotropic (TRISO) particles to enhance safety. The FCM fuel assembly is a double heterogeneous system. The conventional self-shielding calculation methods cannot treat the DH effect. In this paper, three methods based on equivalent homogenization of the TRISO particle and the matrix are studied and compared: the hyper-fine energy group cross sections (XSs) homogenization based hyper-fine energy group method (HHM), the hyper-fine energy group XSs homogenization based subgroup method (HSM) and the subgroup XSs homogenization based subgroup method (SSM). These methods are implemented in a high-fidelity neutronics code NECP-X. Numerical results show that these methods are able to treat the double heterogeneity of the FCM fuel. The precision of the HHM and HSM is higher than that of the SSM.

Fractional Vegetation Cover (FVC) is an important parameter for soil erosion equation. The Fractional Vegetation Cover of typical soil erosion county in red soil region of South China was calculated by parameter revision method (PRM) and fusion method (FM).The results of the two methods were compared from two parts of FVC level and 24 half-months FVC. The results show that the FVC level calculated by PRM was concentrated in high level, and that calculated by FM is mainly in medium-high level and high level. The time variation of FVC in 24 half-months calculated by the two methods was the same, but the majority of FVC value calculated by PRM was higher than that calculated by FM. It is better to choose FM method to calculate FVC in estimating soil erosion.

The article shows the advantages of the Van-Rijn method from the analysis of existing calculation methods for determining the sediment discharge. Based on the results of laboratory studies and the Van-Rijn dependence, dependence was obtained to determine the discharge of bottom sediment, taking into account the establishment of the channel slopes. The resulting dependence is compared with the dependences obtained by other researchers, and these comparisons show good convergence between them.

The safety accident of indoor natural gas supply system is the process of natural gas leakage and diffusion, most of which are turbulent processes affected by many factors. When the natural gas leaks into the indoor confined space, it will mix with the air to form a mixture. When the oxygen in the natural gas and the air reaches a certain concentration range, combustion or explosion will occur when it meets the ignition source. This paper mainly introduces the influencing factors and calculation methods of the explosion limit of natural gas, and analyzes the calculation methods of the explosion limit of multi-component combustible mixed gas.

The article presents a description of the methodology for obtaining data on the physical properties of rocks that compose the sides of the open pit for technological optimization of drilling and blasting operations. The methodology is based on field measurements and calculation methods for determining the hardness of rocks at a chrysotile asbestos deposit, which is being mined by an open pit. The physical properties are obtained by comparing a priori geological data with the values of electrical resistivity and the velocities of elastic waves in the rocks. Based on these data, the values of the Young’s modulus are calculated, which characterizes the strength of the rocks composing the array.

Cargo securing on a railway platform, elastic and retention fasteners, longitudinal transport force of inertia, forces in elastic fastenings. Purpose: The paper presents the calculation of the longitudinal transport force of inertia; determines the longitudinal force perceived by the elastic elements of the cargo securing; determines the reactions of retention bars depending on the number of bars and fasteners (nail); calculates the sum of all holding forces; calculates the forces in the elastic fasteners when exposed to longitudinal forces. Research methods: To determine the forces in the cargo securing devices, existing calculation methods are used. Moreover, the formulas of these techniques are presented in a form convenient for calculation. Main results: The paper proves that according to the existing method, the force in all elastic cargo fasteners under the influence of longitudinal forces has the same value, regardless of the different arrangement of the geometric parameters of the fasteners in space. The forces in them are more than 1.6 times higher than the permissible values. The calculations of forces in the elastic fasteners, which are performed by the specified method, are given. The results of the comparative analysis showed that the forces in all wire fasteners, in contrast to the existing calculation method, have different values. However, the strength of the second pair of wire fasteners of both one and the other direction is not ensured - the force in them more than two times exceeds the permissible value (61/24.8≈2.5), which will result in their destruction during the cargo transportation. Conclusions and their significance for the industry: Existing calculation methods do not provide guarantee strength of cargo fasteners. In the future, to calculate the fastening of cargo by shippers in the railway industry, a new calculation procedure should be applied for the allocation and fastening of cargo on the car.

At present, there is a lack of regional comprehensive energy multi-dimensional evaluation system and calculation of different quality energy in the energy efficiency evaluation of regional integrated energy system. Based on this, this article carries out research on multi-dimensional energy efficiency evaluation index system and evaluation methods. First, this article form quantifiable evaluation indicators from the aspects of energy supply subsystem energy efficiency, energy conversion subsystem energy efficiency, grid energy efficiency, economic benefits and social benefits, and clarify the calculation methods of each evaluation indicator. Then this article calculate the indicator combination weight. Finally, a multi-dimensional energy efficiency assessment method for a regional integrated energy system is proposed, and an example is used to prove the effectiveness of the method.

Inaccuracy of the existing methodology for calculating cargo fastening. Cargo fastening by flexible and retention elements. The paper should define the “shearing” force across the car as the sum of the transverse transport inertia and wind load, taking into account the safety factor from tipping over; determine the transverse force perceived by the means of securing the load, taking into account the reaction of the retention bars of only one direction; calculate the forces in the elastic fasteners when exposed to shearing forces, taking into account the geometry of the fasteners according to existing methods. The research methods are based on the basic law of dynamics for the relative motion of a material point, where the transverse and vertical transferring inertia forces are formally assigned to external forces. The paper proves that according to the existing methodology, the force in all elastic cargo fasteners under the influence of transverse forces has the same value, regardless of the different arrangement of the geometric parameters of the fasteners in space. This is not true. The calculations of forces in the elastic fastening elements according to Appendix 8 of the existing methodology are given. Under the influence of transverse forces, the strength of the first and second pairs of elastic fasteners, both one and the other direction, are not provided by the method of Appendix 8 - the forces in the fasteners are greater than the permissible one (24.8 kN). Existing calculation methods do not ensure the strength of the cargo fastening elements.

The article presents the calculation methods for cycle harvesting of milled peat. They are recommended for the three flow sheets of milled peat production: (a) a method based on a mechanical extraction by means of tanker harvesters; (b) a separate method of peat harvesting and transporting to large stacks and (c) a method based on pneumatic peat harvesting. Positive and negative aspects of the given methods are described and the improved calculation methods for cycle harvesting of milled peat are offered. The proposed methods take into account the weather conditions of a peat production region, the decrease in the initial moisture in the second and subsequent cycles after precipitation, due to the loss of fragmented peat from the previous cycle. A drying rate reduction factor is introduced into calculations in view of the uneven spread of milled crumbs. The performed calculations show that the reduced to 15% cycle harvests are possible to use in a design in comparison with those calculated by the previous technical design standards.

A scheme of membrane pneumatic mechanism of shaking bag filter for cleaning the air from dust is developed. The research findings of dynamics of air mechanic vibratory bag filter system are shown. The concept of revised methods for calculating main parameters of membrane pneumatic vibratory mechanism of the bag filter regeneration is developed.

To maintain a comfortable life it is necessary to pay special attention to environmental aspects. This issue is as relevant for small towns as it is for big cities. The most important tasks are studies of wastewater treatment based on the principles of energy efficiency. The article presents research on the choice of loading material (methods of selection and analysis of loading material). Also described is effective wastewater treatment technology from nitrogen compounds, methods of intensification of the biofilters. Technological schemes are given. The main attention is paid to the study of the four-zone scheme, in which the processes of denitrification-nitrification occur sequentially. Along with the control reactors with the sanitary and chemical analyses, implemented regular monitoring of the microbiological investigations of biomass, using light and electron microscopy. An energy-efficient solution for deep wastewater treatment using biofilters has been developed. Calculation methods are given. The studies will significantly reduce the amount of energy consumed, the cost of processing precipitation. And the achieved effect of wastewater treatment will prevent eutrophication of water bodies and therefore reduce the cost of drinking water treatment.

Composite materials consisting of several phases are widely used in modern construction. Numerous experiments have shown that the properties of structurally heterogeneous materials can differ significantly from those of the individual components making up the composition. Besides, rapidly changing coefficients of differential equations describing such composite materials greatly complicate the solution of boundary value problems even with the help of computer calculation methods. Therefore, the homogenization method is used. In this paper the two approaches propose to obtain in explicit analytical form the effective model of the problem of loading a heterogeneous pipe made of layered material, provided that the elastic properties of the material depend only on the distance from the center of the section of the pipe. We point to a method that obviously leads to an analytical result. It follows from the article that it is possible to choose the function that determines the structure of the “winding” in such a way as to obtain the stiffness characteristics of the pipe as close as possible to the desired with fixed mass fractions of the materials used. A similar approach can be applied to the study of creep properties of pipes made of composite materials.

The paper presents application of equivalent temperature for design of asphalt pavements. The calculation methods of equivalent temperature: the Shell method, the French method, the methods that use the AASHTO and the Asphalt Institute fatigue criteria were presented. The results of calculations of equivalent temperature for Polish climatic conditions were presented and discussed. It was shown that different asphalt pavement design methods and utilization of Polish climatic data resulted in various calculated values of equivalent temperature that could be used in the design process.

Cycloid reducers are gear trains which can be classified as planetary transmissions. These transmissions have a very wide range of uses in industry in transporters, robots, satellites, etc. This research presents a comparative analysis of three analytical methods for determining cycloid drive efficiency. The paper explores every mathematically formulated method and compares them to experimental results from literature. The presented methods for determining efficiency have a common property, in that they all determine losses due to friction on the bearing cam surface of the shaft, the rollers of the central gear and the output rollers. The calculation of efficiency values is done for standard power values. The methods differ primarily in the way they calculate losses. For each method of calculating efficiency there is an analysis of pros and cons. The paper concludes with suggestions as well as possible directions for further research.

Currently, many authors have studied the uniform axisymmetric pressure head laminar and turbulent movement of water in hydraulic smooth and rough (with uniform roughness) pipes of circular cross-section. The results obtained in the study of a plane-parallel turbulent flow in pressure canals allows here only to outline the structure of the corresponding dependencies and to clarify the simplest case of unpressurized fluid movement, when this movement can also be reduced to plane-parallel or, in other words, to movement in a canal of infinitely large width with a flat bottom. In all other cases, the only way to solve the problem is an experiment. The construction of numerous free-flow watercourses and machine canals of pumping stations requires scientifically based calculation methods.

Ecological water replenishment is the part of ecological flow deducting the remaining local existing water that needs to be recharged by other water sources. It has become the basic basis for water resources development and utilization and water affairs coordination. Ecological flow is a complex concept with numerous calculation methods and obvious regional differences. In view of the characteristics of the Mintuo River Basin, especially the problem that the extensive economic development exceeds the environmental carrying capacity of the river, considering the lack of natural rainfall, this paper recommends a one-dimensional water quality simulation method that maintains environmental capacity. Taking Jingyan County as a representative, a case study was carried out. The river was divided into several sections according to the water function zoning, and the water quality of each section was simulated to determine the section and the total river water replenishment, and through compared with the traditional calculation method of water conservancy planning, the rationality and benefit of the period are analyzed.

The article presents the results of testing and FE-modelling of rods calculated for the central and eccentric compressive load. More than 600 tests have been analysed over the past 100 years, including made by author, in a wide range of slenderness made of steels with a yield strength of up to 1000 MPa. It is established that the existing Russian calculation methods allow us to accurately determine the bearing capacity of the rod for steel of any strength. Verification of calculation method was carried out not only by stresses and ultimate load-bearing capacity, but also by the deformations of the tested rods. It is established that for H-beams and thin- walled pipes, clarification of the design codes is required to be able to design cost-effective designs, since the code formulas give a margin. This is especially true for elements of low flexibility with small eccentricities. To clarify the codes, a method for modelling a three-line diagram of steel operation, verified with the test results, is proposed.

The urgency of the issue is the development of the Garagum desert, which occupies 80% of the land resources of Turkmenistan. The aim of the research is to supply the desert regions of the Garagum with energy using solar energy technologies and installations. The research task - to determine the solar-energy resource potential using innovative methods of calculation in the design, creation and implementation of efficient solar energy technology and equipment. Methodology. To determine the gross, technical, economic and ecological potential, the natural and climatic conditions of the Northern Garagum are taken into consideration. Research methodology - used meteorological data, processed by laws of physics and mathematical calculation methods for thermal and photoelectric converters. Research results. The theoretical and methodological calculations of the gross, technical, economic and environmental potentials of solar energy are estimated, the energy efficiency of solar radiation is determined, and the optimal solar collector inclination angles for the Northern Garagum are calculated. Discussion and conclusion. As a result of the research, the resource potentials of solar energy were obtained, converted into thermal and electrical energy, kW•h/m2 per year: gross - 1844.6; technical - 1227.58 and 244.85; economic - 1354.58 and 270.25. Environmental potentials, CO2, kg / year: 784.96 and 156.6. The most effective for the use of solar collectors in the Northern Garagum for months of the year with an angle of inclination is: 60 degrees - January, February, November, December; 45° - March, October; 30° - from April to September.

This article presents an assessment of the external thermal load on the life support system of a solar aircraft under extreme operating conditions. The calculation was carried out for the maximum and minimum possible heat flows in the key points of the aircraft flight. In this article the conditions on the Earth’s surface and at the operating altitude of the aircraft were taken as calculated. The dependence of the quantitative changes in the heat load on the aircraft from altitude was revealed, taking into account changes of thermal properties of the environment and mechanisms of heat transfer.

In this study we analysed the climatic conditions for infiltration estimation, different calculation methods and infiltration impact on heat load for heating systems dimensioning. To determine the wind conditions at low air temperatures of the coastal- and inland climatic zones in Estonia, 42 years of climatic data for Tallinn and Tartu were investigated. Calculation models with detailed air leakages were constructed of a single and two-storey detached house using dynamic simulation software IDA ICE. Simulations were carried out with the constructed calculation models, simulating various wind and sheltering conditions to determine the heating load of the buildings under measured wind conditions at the design external air temperatures. The simulation results were compared with results calculated with European Standard EN 12831:2017, methodology given in the Estonian regulation for calculating energy performance of buildings and with simulations using the default settings in IDA ICE based on the ASHRAE design day conditions. The percentage of heat losses caused by infiltration was found as 13-16% of all heat losses for the studied buildings. Simulations with historical climate periods showed that even in windy weather conditions the heating system dimensioned by the methods analysed may not be able to provide the required indoor air temperature. Analysis using the coldest and windiest periods showed that when systems are dimensioned by the studied methods, the highest decline in indoor air temperature occurs on the windiest day and not on the coldest day. The impact of high wind speeds and low sheltering conditions resulted up to 50% of all heat losses.

Combi boilers offer an economic alternative to individual single function gas boilers and instantaneous water heaters. These gas appliances allow for producing thermal energy for two heating purposes (space heating and hot water preparation). For this reason these compact and highly efficient devices are becoming increasingly popular in many residential buildings. The application of such heating systems often requires an adequate approach for determining the natural gas demand. The literature indicates several methods for this purpose, which often differ significantly. Differences in calculated results seem to be the main problem with these methods. Unfortunately, the selection of the above-mentioned gas appliances always causes overestimation of natural gas demand. This is mainly due to the fact that many calculation methods contain incorrect gas demand coefficients. Therefore, this paper presents various methods for estimating gas consumption for multi-family buildings. It provides discussion and analysis of various calculation methods for residential buildings equipped with two types of gas appliance. The performed analysis made it possible to indicate the most reliable methods of gas demand calculation.

This paper expounds the background and significance of the national standard of the development on the minimum allowable values of energy efficiency and energy efficiency grades for submersible pushing-flow agitator and rotary aerator in wastewater treatment, and introduces the general principle of the standard, the determination of the minimum allowable values of energy efficiency, the division of the energy efficiency grades for them, as well as the testing and calculation methods. It hopes to eliminate the production of the high energy consumption sewage treatment equipment, and enhance their level of the energy efficiency effectively through development and implementation of the national standard.

Electricity that produced by renewable energy sources are countinously increased, but some place in Indonesia have not utilize the renewable sources maximally, for instance Kolorai, South Morotai. Based on data from NASA, solar radiation in kolorai is around 5,99 kWh/m2/day, so solar power plant is one of solution to solve electricity needs in remote area like Kolorai. Futhermore, in solar power plant project, determining the load profile and designing the stand alone PV with simulation is important to make a great system. So the optimal methods are needed to build those system, the methods that have higher energy output, less excess energy, dan have a low Net Present Cost. In this paper, Australian/New Zealand standart and manual calculation are used to create an economical design. The result of the HOMER simulation shows that using Australian/New Zealand standart have a suitable result with excess electricity value is 8,56% and Net Present Cost is 1.439.160.000 rupiah.

The construction of a civil engineering work requires many preliminary studies as well as various calculation methods to give an assessment or a forecast of the state of the rock in place and the behavior of the structure in its real environment and under various conditions (construction phase, service and operating phase). The present work concerns the access zone of the Dar-El-Oued tunnel, located on the national road n°43 about 40 km West of the city of Jijel (northeastern Algeria). The geotechnical study of this tunnel was carried out following the classification methods relating to underground structures. Through the results of this study we have determined the influence of land pressures on the mechanical behavior of the ground, which allowed us to measure the state of stress in the rock and to make a comparison between the results of the measurements of convergence and that of numerical modeling. On the other hand, the influence of the velocity of vibration induced by explosive shots has been discussed in order to check the stability of the face as the digging progresses. From the results obtained, it can be said that the surface displacements of the soil are relatively small compared to those determined by the numerical model at the level of the vault and the slab. Note the good agreement between the results provided by our numerical model and those obtained in-situ.

The requirements concerning energy performance of buildings and their internal installations, particularly HVAC systems, have been growing continuously in Poland and all over the world. The existing, traditional calculation methods following from the static heat exchange model are frequently not sufficient for a reasonable heating design of a building. Both in Poland and elsewhere in the world, methods and software are employed which allow a detailed simulation of the heating and moisture conditions in a building, and also an analysis of the performance of HVAC systems within a building. However, these systems are usually difficult in use and complex. In addition, the development of a simulation model that is sufficiently adequate to the real building requires considerable time involvement of a designer, is time-consuming and laborious (Menberg et al., 2019) [1]. A simplification of the simulation model of a building renders it possible to reduce the costs of computer simulations. The paper analyses in detail the effect of introducing a number of different variants of the simulation model developed in DesignBuilder on the quality of final results obtained. The objective of this analysis is to find simplifications which allow obtaining simulation results which have an acceptable level of deviations from the detailed model, thus facilitating a quick energy performance analysis of a given building.

Composite materials consisting of several phases are widely used in modern construction. Numerous experiments have shown that the properties of structurally heterogeneous materials can differ significantly from those of the individual components making up the composition. Besides, rapidly changing coefficients of differential equations describing such composite materials greatly complicate the solution of boundary value problems even with the help of computer calculation methods. Therefore, the homogenization method is used. In this paper the approach propose to obtain in explicit analytical form the effective model of the problem of loading a heterogeneous pipe made of layered material, provided that the elastic properties of the material only depend on the distance from the center of pipe cross section. We point to a method that obviously leads to an analytical result. It follows from the article that it is possible to choose the function that determines the structure of the “winding” in such a way as to obtain the stiffness characteristics of the pipe as close as possible to the desired with fixed mass fractions of the materials used.

Influence compliance of node connections are not taken into account fully in the existing calculation methods. Basically, this is because of insufficient three-dimensional interference knowledge of elements of thin-walled steel frames. In practice, the structural analysis of the LSTC is usually made with the help of design diagrams with articulated or rigid joints connection elements, therefore, real behavior of structure is not taken into account, as the compliance units may lead to substantial redistribution efforts. Researches in clarifying the design diagrams allow to calculate the steel thin-walled structures with more accuracy and to improve the economic efficiency of design solutions. Thus, the purpose of the study is to determine the qualitative and quantitative characteristics on the basis of experimental and numerical studies that affect the loss of local stability in joints, taking into account the compliance of node connections.

The paper analyzes some of the psychological problems of the economic faculties’ students arising in the course of study of mathematical disciplines. These problems are primarily related with the lack of students’ awareness, misconception about the calculation methods in their future profession, low motivation and performance, math anxiety, etc. They makeadditional difficulties which impede successful mastering of sophisticated material. Based on the experience of mathematical disciplines teaching, the paper provides some possible solutions to these problems with the lecturer who has to play an important role. The lecturer should orientate students towards serious and profound knowledge of economic and mathematical methods, create conditions for students’ active participation in the educational process and provide them with comprehensive assistance in overcoming difficulties.

The paper shows how safety criteria of nuclear power plants with reactor RBMK can be defined based on analytical, numerical and mixed calculation methods using data about strength characteristics of materials with the course of time.

La calorimetrie est la meilleure technique disponible pour mesurer de facon absolue la dose absorbee. Les calorimetres a eau et en graphite sont utilises comme reference dans la plupart des laboratoires de metrologie des rayonnements ionisants. Le LNE-LNHB dispose d'un savoir-faire reconnu dans la fabrication et la mise en œuvre des calorimetres en graphite et equivalent tissu. Le calorimetre en graphite est aujourd'hui le dosimetre de reference pour les faisceaux de photons et electrons au LNE-LNHB. Associe a une procedure de transfert du graphite vers l'eau, il mene a la reference de dose absorbee dans l'eau qui est la grandeur de reference en radiotherapie. Un calorimetre a eau a ete recemment developpe au LNE-LNHB afin de diversifier les methodes permettant d'etablir une reference en termes de dose absorbee dans l'eau.

The paper compares various methods for computing the equivalent stress amplitude for stress cycles of non-zero mean value in stress-life fatigue prediction. A set of 11 calculation methods is evaluated. In addition to formulations based on common static or fatigue properties, the Walker formula and the generalized Linear formula are included in the investigation. These two methods use an optimization routine to find the material parameters. The final response of the methods is compared and discussed. The Walker method provides a better solution. The generalized Linear method produces inferior results, i.e. the linear fit of the segment of the Haigh diagram is not an optimal solution.

For the last decades there emerged a vast number of buildings and structures erected with the use of sandwich panels. The field of application for this construction material is manifold, especially in the construction of fire and explosion hazardous buildings. In advanced evacu-ation time calculation methods the coefficient of heat losses is defined with dire regard to fire load features, but without account to thermal and physical characteristics of building envelopes, or, to be exact, it is defined for brick and concrete walls with gross heat capacity. That is why the application of the heat loss coefficient expression obtained for buildings of sandwich panels is impossible because of different heat capacity of these panels from the heat capacities of brick and concrete building envelopes. The article conducts an analysis and calculation of the heal loss coefficient for buildings and structures of three layer sandwich panels as building envelopes.

The proper level of comfort conditions is one of the main goal when designing HVAC systems in buildings. It influences our self-being, our health and productivity. Thermal comfort is a complex issue and relates to indoor air parameters and personal factors. The publication presents the outcome of the research undertaken in one of the lecture room at Wroclaw University of Science and Technology, Poland. It consisted of measurements of comfort parameters, questionnaire survey and PMV and PPD calculations based on different approaches.

Masonry is often used in the most of reinforced concrete structure constructions as a filling material that is important on structural characteristics. Structural contribution in the calculations was neglected or misunderstood, mainly due to the lack of a practical calculation methods and an appropriate regulatory tool.The analysis of frames filled with masonry is very complex. This complexity is linked from one part to the difference in the nature of elements and its behavior that make up the masonry itself (brick and mortar) and their interaction, and on the other part, for the large dispersion that characterizes the bricks as well as the execution's quality parameters which make it difficult to define reliable criteria for the masonry. The objective of this work is to experimentally highlight the influence of the hollow brick masonry filler, commonly used in Morocco, on reinforced concrete frames subject to lateral stresses, to deepen understanding the seismic behavior of the masonry structures by evaluating the structural performance of a specimen wall. These experimental results will be compared to those found by modeling prototypes, using SAP 2000 software, based on various approaches and models as well as other results deduced from the other researchers. The experimental study was carried out according to standard NF EN 1052-3 on two reinforced concrete frames, of dimensions (2m X 1.6m), the one with the masonry filling, and the other without filling in order to determine the initial characteristic resistance to the shearing of the masonry walls. The obtained results showed that a filling has a beneficial effect on rigidity which can be doubled compared to an empty frame. in the same way the lateral resistance. But this effect is much contrasted; it depends a lot on the characteristics essentially of the materials (bricks and concrete). This is the main reason, which justifies the divergence of the results deduced from the nine models that we used.

The purpose of the article was to compare selected calculation methods regarding shear strength in reinforced concrete beams without web reinforcement. Several calculation methods were tested. This included codes: PN-EN 1992-1-1:2008, ACI 318-14 andfibModel Code for Concrete Structures 2010. The analysis also consists of authorial methods published in technical literature. Calculations of shear strengths were made based on experimental works found in literature. The shear strength ratios Vtest/Vcalcwere chosen to be the yardstick of comparison, where Vtestis the experimental shear strength and Vcalcis the calculated shear strength. A wide range of variables including shear span/depth ratio, compressive strength of concrete, longitudinal steel percentage helped to verify the applicability of calculation methods. Although most of authorial techniques proved to be unstable, they succeeded to show that codes’ formulas for shear strength may still be improved. The presented article is a part of Authors’ long term research in the matter and a new chapter of their study now concerning beams without web reinforcement.

International audience; Two methods are proposed in the following in order to calculate allotropic phase changes. We take into account only the consequences of the volume variation in a same way as in the Greenwood and Johnson’s works. In the 80’s, Leblond proposed to identify the elasto-plastic evolution law by considering the growth of a hard spherical inclusion in a soft matrix. In the first part, we propose to extend the Leblond’s model by considering also the growth of the soft inclusion in the hard matrix that is closer to the end of a cooling transformation. The second part is dedicated to a finer modeling where the phase front is explicitly represented by level sets. The front propagation equations are solved by finite elements and the mechanical simulation is based on the eXtended Finite Element Method in order to avoid costly remeshing.; Nous proposons deux types de modélisations adaptées au calcul de changements de phase allotropiques. Seules les conséquences induites par la variation de volume sont prises en compte, de façon identique à ce que l’on trouve dans les modèles de Greenwood et Johnson. Dans les années 80, Leblond proposa un modèle basé sur la croissance d’une sphère de phase dure dans une matrice plus molle afin de déterminer les lois d’évolutions élasto-plastiques. Dans une première partie, nous proposons d’étendre le modèle de Leblond en prenant également en compte la croissance de la phase molle dans une matrice de phase dure, ce qui correspond à la fin de transformation dans le processus de refroidissement. La seconde partie est consacrée à une modélisation plus fine où l’on représente explicitement le front de transformation par fonctions de niveau. Les équations de propagation du front sont résolues par éléments finis et la simulation mécanique utilise la méthode des éléments finis étendus afin d’éviter les coûteux remaillages.

METAS realise l’etalon primaire de la dose absorbee dans l’eau pour les faisceaux d’electrons de haute energie entre 5 MeV et 22 MeV avec un dosimetre chimique base sur une solution de Fricke. Cette realisation comprend deux etapes. Tout d’abord, une experience d’absorption totale d’un faisceau monoenergetique etroit d’energie et de charge connues permet de determiner la reponse de la solution de Fricke a la dose absorbee. Ensuite, l’irradiation de sachets de solution dans des faisceaux de qualites therapeutiques assure le raccordement metrologique des etalons secondaires. Certaines corrections appliquees aux valeurs mesurees sont obtenues a l’aide de simulations Monte Carlo. Les pertes dues principalement a l’emission de Bremsstrahlung lors de l’experience d’absorption totale dependent de l’energie des electrons et de la taille du recipient de solution de Fricke, et sont comprises entre 2,7 % et 8,2 % de l’energie du faisceau incident. Les facteurs de transfert pour obtenir la dose absorbee dans l’eau a partir des mesures des sachets varient faiblement avec l’energie entre 0,58 % et 0,80 %.

Les methodes d'homogeneisation ont ete utilisees de facon assez courante dans l'industrie nucleaire, en particulier pour la modelisation des faisceaux de tubes. L'application de cette approche a la modelisation numerique d'un reacteur nucleaire, avec prise en compte des effets de couplage et de confinement induits par la presence des structures internes du reacteur, est etudiee dans le present article. La modelisation est ainsi basee sur une approche homogeneisee de l'interaction fluide/structure entre les structures internes, reparties de facon periodique dans le reacteur, et le fluide contenu entre la structure constituant l'enveloppe resistante et la structure de supportage du cœur. Les bases theoriques de l'approche homogeneisee sont rappelees dans un premier temps et la methode est ensuite detaillee dans le cas de structures rigides periodiques. La validation numerique de l'approche couplee est etablie par comparaison entre une modelisation tridimensionnelle "complete" du reacteur avec detail de la geometrie des structures internes et des espaces fluides et une modelisation bidimensionnelle "reduite" utilisant un fluide homogene equivalent. L'importance des effets de confinement est ainsi mise en evidence dans le cas industriel etudie.

La methode de calcul Monte Carlo est reconnue aujourd’hui comme l’algorithme pouvant modeliser au plus pres les phenomenes physiques lies aux depots d’energie dans un milieu. D’ou l’interet d’utiliser cette methode dans la planification de traitement du cancer par rayonnement, les systemes de planification traitement (TPS) existant etant limites dans la precision des calculs pour certains cas bien specifiques. Dans cette approche, nous nous interessons a la validation du code de calcul Monte Carlo GATE pour les applications dosimetriques en physique medicale. Cependant, l’utilisation de la methode Monte Carlo pour des geometries complexes ou des images de haute resolution necessite de nombreuses heures de calculs. En effet, un resultat precis ne peut etre obtenu qu’en generant beaucoup d’evenements. Nous etudions donc les capacites de la grille de calcul de maniere a reduire le temps de calcul en deployant nos simulations avec GATE sur un environnement de calcul distribue.

This contribution presents new results related to the aircraft crew exposure onboard aircraft of Czech air companies. First, the results of long term monitoring onboard of an aircraft of Czech Airlines are presented. In the period May–December 2005, 494 individual flights have been followed using MDU-Liulin Si-diode based spectrometer, together with thermoluminescent and track detectors. The results of measurements are analyzed and compared with those of calculation performed with CARI6 and EPCARD3.2 codes. Monitoring period represented about 4.6 times more than usual annual engagement of an aircrew (600 hours). Total effective dose during these 2 755 hours was between 11 and 12 mSv, following the considered method of evaluation. Both the measuring and calculation methods correlate well. This fact leads to confirmation of the routine method evaluating the level of aircraft crew exposure using CARI6 code as correct for this purpose. Second, the results of individual monitoring of aircrew members obtained during few last years by this routine method are presented; general tendencies of aircraft crew onboard exposure of Czech air companies are outlined. The contribution of aircrew exposure to total occupational exposure in the Czech Republic represents about 20%.

La radiotherapie interne ou vectorisee consiste a injecter aux patients des radiopharmaceutiques afin de delivrer des doses de rayonnements aux tumeurs ou organes cibles. La realisation d’etudes dosimetriques est necessaire pour chaque patient traite par radiotherapie vectorisee ainsi que pour les sujets contamines par inhalation, blessure ou ingestion. Afin d’atteindre la precision requise dans de tels cas, nous avons developpe une methode dosimetrique, basee sur le code Monte-Carlo de transport des particules MCNPX. L’anatomie de chaque patient ou sujet contamine est prise en compte sous forme d’une geometrie voxelisee creee a partir d’images tomodensitometriques (CT) ou de resonance magnetique (IRM). Cet outil baptise ŒDIPE (acronyme d’outil d’evaluation de la dose interne personnalisee) permet de realiser des etudes dosimetriques a l’echelle des organes et du voxel. La validation d’un tel outil est complexe car les sources de variations du calcul dosimetrique sont multiples : methodes de calcul, definitions et representativite de la geometrie. L’etude presentee ici a pour but de valider l’outil ŒDIPE par comparaison de ses resultats avec des mesures experimentales obtenues a l’aide de fils thermoluminescents. La comparaison des doses moyennes calculees et mesurees est satisfaisante. Cependant, la mesure et le calcul des distributions spatiales de dose le long des fils thermoluminescents, bien qu’ayant des allures comparables, presentent des ecarts significatifs. Cela est du au fait qu’il est impossible de faire correspondre exactement une portion de fil a un voxel donne.

L’anthroporadiametrie pulmonaire est une methode de choix pour la surveillance des travailleurs de l’industrie nucleaire exposes a un risque de contamination interne. Un certain nombre de difficultes est cependant rencontre avec cette technique, difficultes principalement liees aux conditions d'etalonnage, conduisant a des incertitudes et des erreurs systematiques importantes sur les resultats. En effet, l’utilisation de fantomes physiques d'etalonnage reste un facteur limitant et engendre d’importantes corrections en vue d’une extrapolation a un individu donne. Une perspective prometteuse pour diminuer les erreurs systematiques consiste a etalonner de facon individuelle le systeme de mesure avec des fantomes numeriques specifiques aux personnes a mesurer. Dans ce but, une interface appelee ŒDIPE (Outil d’Evaluation de la Dose Interne PErsonnalisee), associant fantomes numeriques voxelises et calcul Monte Carlo (MCNP), a ete developpee au Laboratoire d’Evaluation de la Dose Interne de l’IRSN. Le but de l’etude proposee ici est de montrer le potentiel de cette technique pour la simulation realiste de la mesure anthroporadiametrique des actinides dans les poumons. Apres la presentation de l’interface ŒDIPE pour la mesure pulmonaire, sa validation est presentee en utilisant un fantome d'etalonnage couramment utilise (fantome Livermore). Ensuite, une comparaison de differents fantomes thoraciques d’etalonnage par rapport au fantome numerique d’une personne (fantome de Zubal) a ete effectuee afin de montrer les variations d’etalonnage engendrees par les differences morphologiques de ces fantomes et donc la necessite d’un etalonnage plus specifique par individu. Enfin, des approches de contaminations inhomogenes ont ete realisees afin de montrer l’interet de la technique pour l’etude des variations des facteurs d'etalonnage en fonction de la repartition des radioelements dans les poumons. Les differents resultats montrent le potentiel de cette technique pour l'etalonnage realiste des installations anthroporadiametriques.

We describe a method for computing theoretical photometric amplitude ratios for a number of modes of nonradially pulsating subdwarf B stars in both SDSS and UBVR systems. In order to avoid costly solutions of the non-adiabatic non- radial pulsation equations, we have adopted the adiabatic approximation. We argue that this is a valid approach, at least for the V361 Hya stars, because observations show that the temperature perturbations dominate the radius perturbations in the flux variation. We find that for V361 Hya stars, low-degree (� = 0, 1, 2) modes may be difficult to distinguish using optical photometry. However, the high degree modes (� = 3, 4) are relatively well separated and may be distinguished more easily. We have also computed the amplitude ratios for a number of modes in PG 1716+426 stars. For these stars, the amplitude ratios for low degree modes (� = 0, 1) are well resolved. For oscillations with periods ∼40 min, higher-degree modes (� = 2−4) may also be identified easily from their amplitude ratios. However for longer period oscillations, the � = 3a nd the� = 2, 4 modes approach the � = 0a nd� = 1 modes respectively.

At the end of the 80ies it clearly appeared that the development of a thermodynamic database devoted to the nuclear field was a necessity, and more precisely for the applications in security and severe accident calculation codes in which the data used were simplistic. At the same time the emergence of the CALPHAD method allowed to hope an important progress in the quality and reliability of thermodynamic data for complex thermochemical systems. More than 10 years were required to develop such a database because it was a largescale task. Today NUCLEA allows the thermodynamic properties and equilibria determination in a chemical system with 18 elements: Ag-Al-B-Ba-C-Ca-Cr-Fe-In-La-Mg-Ni-O-Ru-Si-Sr-U-Zr.