Estimation of the Rational Range of Ecological Compensation to Address Land Degradation in the Poverty Belt around Beijing and Tianjin, China

Ecological compensation provides innovative ecological solutions for addressing land degradation and guaranteeing the sustainable provision of essential ecosystem services. This study estimated the ecosystem service value and the opportunity cost of land use in the Poverty Belt of China—around Beijing and Tianjin—from 1980 to 2015 on the small watershed scale, and thereafter estimated the rational range of ecological compensation in this ecologically fragile zone. Results showed that the total ecosystem service value in the study area gradually decreased from CNY 54.198 billion in 1980 to CNY 53.912 billion in 2015. Moreover, the annual total ecological compensation of the whole study area ranged between CNY 2.67 billion and 2.83 billion. More specifically, areas with higher ecological compensation standards are mainly concentrated in the northwestern and northern parts of the study area, with a lower economic development level, while areas with lower ecological compensation standards are mainly located in areas with a relatively high level of economic development, e.g., the southern and southeastern parts of the study area. These results can provide valuable decision-support information for the design and optimization of ecological compensation to address land degradation along with rapid urbanization in the Beijing–Tianjin–Hebei region.

Study of deformation conditions at longitudinal pipes rolling from austenite steel grades

Stainless steels of austenite class 08–12Х18Н10Т have a high corrosion resistance, which stipulates for their wide application in various areas of industry. Technology of pipes production of the steels is rather specific and requires observation of some conditions. It was shown that temperature of a work-piece heating before deformation is an important parameter of the technology. It was noted that for the piercing of a steel work-piece with various chrome content, there is a rational temperature interval. Nonobservation of the temperature can lead to defects formation on internal pipe surface because of earlier destruction and opening of metal cavity during piercing. The choice of the rolling-out scheme has a direct effect on the work-piece forming in cross-sections. Results of hot rolling of Ø37×2,5 tube samples, manufactured of 08–12Х18Н10Т steel and carbon steel of grade 40 presented. The rolling was done at a laboratory mill. As a result of the experiment the lower limit of ovality of rolls grooves was specified for conditions of rolling of pipes from 08–12Х18Н10Т steels by 2-roll scheme. At the rolling with ovality B/H ≤1,07, defects appeared on the internal tube surface in the form of scratches caused by the mandrel. The rational range of ovality of grooves at multi-stand rolling can be from 1.08 to 1.15. According to criterion of groove overfilling by metal for steels 08–12Х18Н10Т, requirements were formed towards the groove width of the first stand of longitudinal rolling mill. The groove width must be larger than the sleeve diameter: for 3-roll scheme – at least by 2–3%, for 2-roll scheme – at least by 7.0–7.5%. Potential advantages of 3-roll scheme comparing with 2-roll scheme for rolling of 08–12Х18Н10Т steels were established as follows: lower probability of grooves overfilling by metal of the work-piece, absence of defects (scratches caused by mandrel), on the tube internal surface at minimal ovality level of 1.07, lower level of transverse pipe wall non-uniform thickness.

Optimization of perishable goods delivery in supply chains with random demand

The article suggests a model for defining a rational range and volume of supply of perishable goods in their supply chains functioning at the time of random demand. In the verbal formulation, the goal of the model is to determine the range and delivery volumes of perishable goods that maximize profits with restrictions on the funds available for their purchase, storage volumes and weight, as well as on lost profits. The formalized representation of the model is determined by the properties of the supplied perishable goods. If these goods are divisible, then the model is formalized as a linear programming problem. In this case, the rational assortment and volume of goods is determined by solving it, for example, using the simplex method.If the goods under consideration are piece (indivisible), they are formalized in the form of a corresponding integer programming problem. In this case, the rational assortment and volume of goods is determined by solving it, for example, based on the branch and bound method. The peculiarity of the model is that it takes into account the stochastic nature of demand for goods, their limited shelf life, as well as the possibility of storing goods and the availability of funds necessary to purchase the next batch.

Improvement of the membrane-free electrolysis process of hydrogen and oxygen production

Renewable energy sources provide an unstable energy flow to the units of an autonomous energy complex. Therefore, in order to use the electrolyzer as an element of the considered complex, it is necessary to determine the optimal range of changes in the current density and evaluate the effect of operating characteristics of the electrolysis process on the evolution of H2 (O2) when the electrolyzer power supply is disconnected for 13 seconds against the background of a continuous base current level. Purpose. The main purpose of the research is to determine the rational range of changes in the current density supplied to a monopolar membrane-free high-pressure electrolyzer, as well as to determine the effect of a discrete current supply on electrochemical reactions during electrolysis. Methodology. Comprehensive studies on the electrochemical processes of water decomposition in alkaline electrolyte with the formation of hydrogen and oxygen in an experimental construction make it possible to cyclically supply power to the electrolyzer with visual control of the considered processes. Findings. The technology of cyclic generation of hydrogen and oxygen, which eliminates the need to use separating ion-exchange membranes, is considered. A rational range of changes in the current density on a membrane-free monopolar high-pressure electrolyzer with the usage of electrodes made of metals with variable valence is established. The influence of the discrete supply of electrical energy to the electrolysis cell is determined depending on the electrochemical reactions occurring on the active iron electrode. Theoretical values of the voltage of the oxidation and reduction of the iron electrode active mass, as well as the voltage on the half-cycle of hydrogen evolution during the electrolysis of water, are calculated. Originality. An increase in the blackout time from 1 to 3 s leads to a corresponding increase in time of the oxidation process on the hydrogen half-cycle by a factor of 2.4. In addition, the total amount of hydrogen (oxygen) released during the corresponding half-cycles remains unchanged and amounts to Practical value. The optimal range of current density for the operation of a membrane-free high-pressure electrolyzer is in the range of 200400 A/m2. Under such conditions, an intense redox process of the iron electrode active mass occurs. Electrical energy consumption in this case is in the range of 3.94.1 kW h/m3. An experimental study on the electrolyzer discrete power supply effect on its ability to generate gas is carried out. This makes it possible to supply electrical energy to the electrolysis cell directly from the primary energy source (sun, wind) as part of the energy technology complex.

Improving the energy efficiency of buildings based on the use of integrated solar wall panels

Frequently used facade glazing makes it possible, on the basis of modern trends in the architecture, to increase the energy efficiency of buildings under construction through the organization of passive solar heat supply. Despite the noted relatively low efficiency of the radiation utilization method recommended for the use, it is possible to increase its indicators by integrating the elements of active solar units in the absorbing layer of the accumulating construction structure. For example, the placement of pipes for the coolant in external enclosing structures will allow year-round exploitation of arrays for passive utilization of solar energy and the use of the obtained heat not only for heating rooms during the cold period of the year, but also for heating water, as well as for absorption chillers in the summer season. The application of the latter contributes to the organization of alternative cooling of the internal blocks of air conditioning systems in the warm period of the year. The listed functions require a different approach in the algorithm of the decisions taken in the design of building structures actively involved in the balance of energy supply. One of the main indicators that determine the possible version of the implementation of the solar radiation utilization system is the achieved temperature potential of the heat flux obtained from the surface of the accumulating layer. The use of the method of sources and the principle of the imposition of fields when solving problems of the depth of embedding and step distance integrated into the surface layer of pipes allows determining the rational range of the values of the specified parameters. This, in turn, is aimed at ensuring the possibility of designing energy-efficient exterior enclosing structures that contribute to the maintenance of the thermal regime required by the multifunctional utilization of solar energy.

Extended Comparison Study a mong lab-Tested HbA1C, ADA’s eGA HbA1C Conversion Model, and eclaireMD HbA1C Prediction Model based on lower Bound and Higher Bound of Measured Glucoses Using GH-Method: Math-Physical Medicine (No. 341)

This paper describes the author’s extended study regarding American Diabetes Association (ADA) recently recommended estimated average glucose (eAG) equation. He conducts a rational range analysis with lower bound and higher bound of different HbA1C values for type 2 diabetes (T2D) conditions by using glucoses collected via finger-piercing test strip method (Finger) and continuous glucose monitoring sensor (CGM Sensor). This study also includes his developed eclaireMD mathematical model of predicted HbA1C and A1C value calculated using the ADA’s eAG A1C conversion equation

Evolutionary Game Simulation on Government Incentive Strategies of Prefabricated Construction: A System Dynamics Approach

Prefabricated construction is a state-of-the-art construction technology of both socio-economic and environmental benefits, but sometimes, it is not welcome due to its high cost. Governments play an important role in deeply promoting prefabricated construction, but its effects are not clear. This paper developed a system dynamics model for investigating and simulating the impacts of government incentive strategies on prefabricated construction by considering the evolutionary game process between the government and contractors. Data of Shanghai, China, is collected for demonstration and validation of the developed simulation model. Results show that (1) the evolutionary stable strategy does not exist in static game process; (2) the rate of adopting prefabricated construction is affected by the level of penalties and subsidies; (3) dynamic incentive strategies can better improve the stability of the evolutionary game process; and (4) the rational range of incentive rate can be obtained. Findings of this study facilitate governments to formulate and improve the incentive strategies of prefabricated construction, thus boosting the development of construction industrialization.

WELDING WITH A MIX OF DISPERSED-HARDENED ALUMINUM COMPOSITE MATERIALS

Установлена возможность применения сварки трением с перемешиванием для получения неразъемных соединений дисперсно-упрочненных алюмоматричных композиционных материалов, армированных наночастицами AlO и SiC. Определен рациональный диапазон параметров режима в зависимости от объемной концентрации упрочняющих частиц. It is possible to use friction welding with mixing to produce non-corrosive compounds of dispersed aluminum composite materials reinforced by AlO and SiC nanoparticles. A rational range of regime parameters is defined depending on the volume concentration of hardening particles.

Using Two Clinical Glucose Measurement Datasets, Finger Glucose As Lower Bound and Sensor Glucose As Upper Bound, to Establish A Rational Range of HbA1c Values for Type 2 Diabetes Patients (GH-Method: Math-Physical Medicine)

This paper describes a rational range of HbA1C for type 2 diabetes (T2D) conditions based on big data analytics of a lower bound from finger-piercing and glucose testing strip method (Finger) and an upper bound from a continuous glucose monitoring sensor device (Sensor). It uses the “eAG” concept defined by ADA to conduct this comparison study.

Justifying the productivity of a grain dryer in the climate of the Southern Urals

The use of grain-drying complexes is established to make possible to start harvesting before the crops are fully ripened, to shorten the harvesting period, to increase the productivity of combine harvesters and reduce production losses. An economic and mathematical model is developed to justify the productivity of grain-drying equipment, taking into account the rate of grain supplied from the field. Simulation made possible to reveal the rational productivity of a grain dryer taking into account a wide range of natural and production factors. The dependence of the operation of combine harvesters on the moisture content of the grain mass is obtained. It is established that the use of crops with different growing periods in crop rotation makes possible to expand the rational range of harvesting equipment and grain-cleaning complexes, to reduce the total cost of production.