Numerical Simulation of Operating Parameters of the Ground Source Heat Pump

Due to the growing demand for new ecological, low-emission heat sources, there is a need to develop new tools for simulating the operating parameters and costs of the implemented solutions. The article analyses the existing solutions for the simulation of heat pump operation parameters, describes the requirements for a modern building—nZEB and proposes a simulation tool based on thermodynamic parameters of the refrigerant. The script allows for deriving simple linear equations that can be used for the overall simulation of a system in which the heat pump is a key part and the efficiency of the entire system depends on its performance. The developed numerical script allows for reproducing the Linde refrigeration cycle and the parameters of its characteristic points. To calibrate the simulation, historical data obtained from the SOPSAR system were used. These data were pre-cleaned (peaks and other obvious measurement errors were removed). The obtained numerical model in combination with ground and air temperatures, anticipated hot water consumption and energy losses of the building can be used to simulate the annual performance and energy consumption of the heat pump. The obtained linear models have an RSMD error of 8% compared to historical data from SOPSAR system for all sets of simulated temperatures.

The Influence of Long and Short Cycle Schemes of Self-Cycling Fermentation on the Growth of E. Coli and S. Cerevisiae

Self-cycling fermentation (SCF), a cyclic process in which cells divide once per cycle, has been shown to lead to improvements in productivity during bioconversion and, often, whole-culture synchronization. Previous studies have found that in some cases, the completion of synchronized cell replication occurred simultaneously with depletion of a limiting nutrient. However, exceptions were also observed when the end of cell doubling occurred before the exhaustion of the limiting nutrient. In order to better understand the underlying mechanisms and impacts of these growth patterns on bioprocessing, we investigated the growth of Escherichia coli and Saccharomyces cerevisiae in long- and short-cycle SCF strategies. Three characteristic events linked to SCF cycles were identified: (1) the completion of synchronized cell replication, (2) the depletion or a plateau of the limiting nutrient, and (3) characteristic points of control parameters (e.g., the minimum of dissolved oxygen and the maximum of carbon dioxide evolution rate). Three major trends stemming from this study and SCF literature were observed: (A) co-occurrence of the three key events in SCF cycles, (B) cycles for which cell replication ended prior to the co-occurrence of the other two events, and (C) cycles for which the time of depletion or a plateau of the limiting nutrient occurred later than the concurrence of the other two events. Based on these observations, a novel definition for SCF is proposed.

КАРКАСНА МОДЕЛЬ ОДНООСНОГО РОЗТЯГУВАННЯ КУЛІРНОГО ТРИКОТАЖУ ВЗДОВЖ ПЕТЕЛЬНИХ СТОВПЧИКІВ

The purpose of this study is to develop a frame model for stretching the weft-knits in the wale direction, suitable for further integration into the algorithm for building a three-dimensional knitwear model in a stretched state and modeling of interactive deformation dynamics. Methodology. Methods of theoretical analysis, basics of knitting theory, topological model of knitwear, methods of geometric modeling and parameterization were used in the research process. Findings. Modeling the physical and mechanical behavior of knitwear in a computer environment is one of the promising ways to increase the level of conformity of knitted products with the requirements of comfort and functionality. However, the complexity of the internal structure, the anisotropy of properties and the instability of the parameters of the loop structure determine the need to find non-trivial ways to solve the problem of mathematical description of the three-dimensional model of the thread, knitted in the knitwear, considering the stretching deformations. During the study, a frame model of a uniaxial stretching of knitwear in the wale direction was developed. The basis of the frame model is the idea of a knitted structure, represented as a logically organized set of elements, each of which is interlaces with other elements in accordance with the topology of knit. The frame of the jersey fragment is described as a set of bars and hinges. The hinges are located at the interlacing points of the loop heads and loop feet, and each rod in the model is an imaginary element representing a complex of force factors that prevent the change of distance between the hinges connected to the given rod. In the process of stretching, the geometrical characteristics of the elements change, while the logical connections remain unchanged. The wireframe model allows to define coordinates of interlacement points in the coordinate system of the sample, relative position of coordinate systems of each elementary fragment, which correspond to given loops, coordinates of characteristic points of a loop for transition to a three-dimensional model of a knitted structure. Scientific novelty. For the first time, a frame model of deformation of the knit, suitable for three-dimensional modeling of its structure, considering deformation of the thrust, was developed. Practical value. The developed model can be used as mathematical support of systems of automated designing of knits.

The Invention and Application of Typical Points-Based Well Log Correlation and Picking Up Technology

This paper proposes a new method called typical points-based well log correlation and picking up technology and provides several related application examples based on this method. The new method firstly determines representative extreme points, typical or characteristic points by analyzing the characteristics of logging curves and lithology of different wells, which are generally representative points with special geological significance, including the points with the best physical properties or tight points. (For example, the maximum flooding surface or exposed surface in a sedimentary cycle, etc.). On the basis of these characteristic points, we carry out stratigraphic correlation and tracking between wells to obtain a data set of a series of characteristic points. From the same characteristic point, all points have the same or similar petrophysical properties, and the logging curve values of these characteristic points are extracted. And then analyze the change trend, distribution characteristics and the internal relationship of the parameters of the data set of each feature point. Based on the data set obtained from the method above, we extended it to the following application areas: 1) Through mathematical theoretical models, two free water level distribution modes and their determination workflows were established, including horizontal and tilted free water levels. 2) Perform data quality analysis and control, especially logging data analysis. 3) Exploratory application in the standardization of logging curves.4) Application in dynamic performance analysis The new method is developed on the traditional stratigraphic correlation method and stratal slicing method (Zeng Hongliu, 1998) and then used for well log data extraction and analysis. It is a practical means and technique for geological analysis. The application effect shows that the it is reliable, convenient and practical.

Mechanical Characteristics and Energy Evolution of Sandstone Three-Point Bending Test

With the increase of underground mining depth in coal mines, the distribution of stress fields in deep mining becomes more complex, and the stress localization characteristics are obvious. In order to obtain the local mechanical properties and energy evolution of sandstone, this article is based on the three-point bending experiment and combined with the localized failure theory to explore the evolution law of stress field, deformation field, and energy field of sandstone specimen under tensile stress during the three-point bending experiment. The results show that during the three-point bending test of sandstone, with the increase of the span of the three-point bending test, the peak stress at the characteristic point shows an increasing trend, and the peak stress has obvious regional characteristics. In the vertical direction, the peak stress at the characteristic points in the upper part of the neutral layer is larger, and the peak stress at the characteristic points in the lower part of the neutral layer is smaller. In the horizontal direction, the peak stress at the characteristic points in the near field is higher, and the peak stress at the characteristic points in the middle field and the far field is smaller. The stress field and the deformation field have a good corresponding relationship. The upper far-field peak strain tends to decrease with the increase of the span, and the upper near-field peak strain first decreases and then increases with the increase of the span. The lower near-field peak strain tends to decrease and then increase with increasing span, and the lower far-field peak strain fluctuates with increasing span. The energy field is dependent on the stress field and the deformation field, showing obvious regional characteristics. The energy storage and release capacity of the upper area are higher than those of the lower area. The overall performance of the loading energy storage, rebound energy release, and crack propagation energy release in different areas can be described as far field < mid-field << near field. The near-field energy at different spans presents the characteristics of two stages. When the span is between 140 mm and 150 mm, the near-field energy shows a rapid decreasing trend, and when the span is between 150 mm and 180 mm, the near-field energy presents an obvious increasing trend.

Theoretical basis for the formation of damaging factors during the coal aerosol explosion

Purpose. Assessing the process of damaging factors formation during the coal aerosol explosion in mine workings on the basis of theoretical research of the explosion of coal dust deposits in order to substantiate promising methods of protecting miners from their impact. Methods. An integrated approach is used, which includes a critical analysis of literature data on the occurrence and development of coal aerosol explosions in mine workings; theoretical research into the state of the gaseous medium at the characteristic points of the development diagram of the coal dust deposits explosion as a result of mining operations based on the laws of classical physics and chemistry. Findings. The main aspects of the explosion mechanism of dust in a powdery state, accumulated on the surfaces along the mine working perimeter, and the formation of such negative factors as the effect of gaseous medium accelerated movement, have been revealed; high temperature formed during coal and methane detonative combustion; increased gas pressure. The revealed aspects of the dust explosion mechanism make it possible to determine the main directions for protection of miners caught in the explosion. The diagram of the development of settled coal dust explosion along the mine working with normal ventilation conditions, taking into account the influence of seismic waves, has been improved. Originality. Analytical dependences, reflecting the value of gas energy at characteristic points of the diagram, have been determined, and the dynamics of the formation of negative factors caused by the explosion have been revealed. Practical implications. Possible ways of protecting miners from the impact of negative factors caused by the coal aerosol explosion and reducing the severe consequences of such accidents are proposed.

Search for identical regions in images using invariant moments

One of the ways to describe objects on images is to identify some of their characteristic points or points of attention. Areas of neighborhoods of attention points are described by descriptors (lots of signs) in such way that they can be identified and compared. These signs are used to search for identical points in other images. The article investigates and establishes the possibility of searching for arbitrary local image regions by descriptors constructed with using invariant moments. A feature of the proposed method is that the calculation of the invariant moments of local areas is carried out with using the integral representation of the geometric moments of the image. Integral representation is a matrix with the same size as the image. The elements of the matrix is the sums of the geometric moments of individual pixels, which are located above and to the left with respect to the coordinates of this element. The number of matrices depends on the order of the geometric moments. For moments up to the second order (inclusively), there will be six such matrices. Calculation of one of six geometric moments of an arbitrary rectangular area of the image comes down up to 3 operations such as summation or subtraction of elements of the corresponding matrix located in the corners of this area. The invariant moments are calculated on base of six geometric moments. The search is performed by scanning the image coordinate grid with a window of a given size. In this case, the invariant moments and additional parameters are calculated and compared with similar parameters of the neighborhoods of the reference point of different size (taking into account the possible change in the image scale). The best option is selected according to a given condition. Almost all mass operations of the procedures for calculating the parameters of standards and searching of identical points make it possible explicitly perform parallel computations in the SIMD mode. As a result, the integral representation of geometric moments and the possibility of using parallel computations at all stages will significantly speed up the calculations and allow you to get good indicators of the search efficiency for identical points and the speed of work

On the induced geometry on surfaces in 3D contact sub-Riemannian manifolds

Given a surface S in a 3D contact sub-Riemannian manifold M , we investigate the metric structure induced on S by M , in the sense of length spaces. First, we define a coefficient [[EQUATION]] at characteristic points that determines locally the characteristic foliation of S . Next, we identify some global conditions for the induced distance to be finite. In particular, we prove that the induced distance is finite for surfaces with the topology of a sphere embedded in a tight coorientable distribution, with isolated characteristic points.

Several Effective Measures for Minus Excess Mortality of COVID-19 in Japan Including Mutual Interrelationships and Long-Term Care Facilities (LTCF)

The impact of COVID-19 can be shown by life expectancy, excess death and total years of life lost (YLL). United States showed life expectancy minus 1.67 years, excess deaths 375,235 and total YLL 7,362,555. The excess death of Japan has remained minus value for long, in which long-term care facilities (LTCF) may contribute. LTCF has characteristic points as i) mutual interrelationships between hospitals, medical societies and prefectural offices, ii) rapid communication channels for regulatory official authorities, iii) high degree of citizenship and cooperation of all Japanese people for daily life and iv) mild lockdown without any punishment with declaration.