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Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction. The method of reliability coefficients with fixed values (declared in regulatory documents) is used as a basic method of limit state verification. However, there is a more general formulation of the semi-probabilistic method, within which the specificity of the design (e.g. information on the variability of actual dimensions, material properties, etc.) and the specificity of the location (e.g. information about climatic loads) can be taken into account more accurately. This method is referred to as the modified (adjustable) partial factor method.Materials and methods. The paper is aimed at the development of the method of reliability coefficients with adjustable values for the design of steel structures and the scientific justification of the parameters of this method. The methodological formulation of this method is based on determining the design values of the basic variables based on the distribution function for a given quantile. In this case, the quantile of the distribution is calculated using the sensitivity coefficients of the basic variables of the first-order reliability method and the target value of the reliability index.Results. The study describes in a general formulation a method of reliability coefficients with adjustable values for the design of steel structures, which allows explicitly taking into account the target reliability level and variability of the basic variables. In the course of the study, the scientific substantiation of the sensitivity coefficients of the basic variables based on the first-order reliability method was performed and instructions on the purpose of probabilistic models of random variables were presented.Conclusions. The analysis of the generalized function of the limiting state of the steel element by the probabilistic method showed that the sensitivity coefficients change significantly with the change in the loading parameter (characterizing the ratio of variable loads to the total), while it changes slightly depending on the type of variable load itself. Sensitivity coefficients can be assumed based on graphs or simplified dependencies presented in this study. Conservatively, the sensitivity coefficient values for the bearing capacity of the steel element can be assumed to be 0.6, for constant loading –0.4 and for variable loading –0.9.

Declining the sintering temperature of enamel coatings is traditionally by reducing the content of network-forming agents (such as SiO 2) and increasing the content of flux (for example, alkali metal oxides), which will lower the density of the [- Si - O -] network structure, and adversely affect the corrosion resistance of enamel coatings. To ensure a low sintering temperature of enamel coatings as much as possible under a high SiO 2 content, it is essential to develop novel enamel coating formulas. However, abundant compositions of enamel coatings cause enormous verification workloads. To address this issue, this paper establishes a relational model of the compositions of enamel coatings and the sintering temperature using the back propagation (BP) neural network algorithm and proposes a formula that meets the requirement of lower the sintering temperature under a high SiO 2 content. When the SiO 2 content is 55 %, the sintering temperature can be diminished to around 400 °C. Furthermore, the influences of common enamel components on the sintering temperature are identified in this paper using the sensitivity algorithm. The obtained general law of formulas is that the total weight value of the formula at low sintering temperatures should be around −0.3. This paper can provide valuable theoretical guidance for subsequent research and expand the application range of enamel coatings. [ABSTRACT FROM AUTHOR]

Identification of, and compensation for, geometric errors is a cost-effective way to reduce the volumetric errors of five-axis machine tools and thus reduce workpiece geometric errors. An adaptive identification method is introduced to directly reduce workpiece geometric errors. We determined the relation between the root-sum-square values of geometric error sensitivity coefficients and workpiece geometric errors. Then, an optimal measurement path minimizing those values was adaptively determined to identify position-independent geometric errors of the rotary axis. We applied our method to improve the radial deviation of the cone-shaped ISO 10791-7 testpiece, as an example. The radial deviations were 22.6 and 27.6 μm in the counterclockwise (CCW) and clockwise (CW) directions, respectively, after compensating for the position-independent geometric errors identified using a common measurement path. These values improved by 27% and 17% to 16.4 and 22.9 μm in the CCW and CW directions, respectively, after compensating for the position-independent geometric errors identified using the optimal measurement path, thus confirming the validity of our approach. [ABSTRACT FROM AUTHOR]

In the unstable conditions of development of the world economy, which occur under the influence of factors of political and economic instability, one of the most important problems of stable functioning and development of the country’s economy is to ensure the stable development of both the kinds of economic activities and enterprises. Since all kinds of economic activity react differently to the instability of the external environment, it is important to analyze the conditions of functioning and the results of the activities of enterprises by the kinds in order to form adequate and adaptive managerial reactions to the tactical and strategic behavior of the latter. The aim of the article is to study and determine the sensitivity of kinds of economic activities to changes in the external environment in order to form adaptive economic behavior of enterprises. In order to achieve this goal, in the course of the research the following scientific methods were used: comparative analysis, graphic analysis, structural-dynamic analysis, coefficient and cluster analysis. The article proposes an algorithmic model of formation of economic behavior of enterprise depending on the level of sensitivity of the certain kind of economic activity. Implementation of the proposed model will allow to form an effective system of managerial decisions on the future behavior of enterprises. The basis for the development of managerial decisions is the analysis of tendencies in the development of kinds of economic activity of the country by the indicator of gross value added, the allocation of cluster groups of kinds of economic activity by the level of their sensitivity. All this will allow to form an effective system of managerial decision-making, which is aimed at maintaining a sustainable attractor of economic development of the enterprise.

Sensors that can provide stability and durability in high-temperature and harsh environments are of great significance for real-time temperature monitoring. Herein, different pyrolysis temperatures of Polymer-derived silicoboron carbonitride (SiBCN) ceramics were fabricated and characterized via SEM, XRD, Raman spectroscopy and TEM. A SiBCN ceramic temperature sensor with excellent sensitivity, accuracy, repeatability, stability and response rate was developed based on the semiconductor characteristics of SiBCN ceramics. The sensor was encapsulated in a stainless-steel casing and its performance was evaluated in the range of room temperature (RT) to 980 °C utilizing a high-temperature resistance detection system. The SiBCN ceramics are typical NTC thermistors with B-values up to 3118 K and provide a sensitivity coefficient of − 3.5 %/K to − 0.2 %/K over the range of RT to 980 °C. A series of examinations verify the outstanding accuracy, repeatability and stability of the SiBCN ceramic sensor. Compared to conventional thermocouples, the SiBCN sensor has faster temperature response rate. In combination with the outstanding high-temperature thermomechanical properties of SiBCN ceramics, it is demonstrated that the designed SiBCN ceramic temperature sensor is suitable for temperature measurement in high-temperature and harsh environments. [ABSTRACT FROM AUTHOR]

Crop evapotranspiration (ET) is one of the most important components in many hydrological processes. The crop reference evapotranspiration (ETo) represents the atmospheric water demand in each crop type, development stage, and management practices. The Penman-Monteith equation in the version suggested by the Food and Agriculture Organization (FAO56-PM), is one of the most used methods to estimate ETo. In several regions of the world, meteorological observations are not always available. The most recent reanalysis database ERA5-Land, released in 2019, can be useful to overcome this limit. The database provides, with a spatial grid of 0.1° latitude and 0.1° longitude, several hourly climate data such as air temperature, dew point temperature, solar radiation, and wind speed components all at 2.0 m above the soil surface, except wind speed components at 10 m, useful to apply the FAO56-PM equation. The objective of this research is to assess the quality of ERA5-Land climate variables data to estimate daily ETo in Sicily, Italy. The effect of the weather station’s elevation associated with the statistical indicators was also evaluated to verify how the morphology affects the measurements. Finally, the sensitivity analysis of the FAO56-PM equation was carried out to identify which climate variables have the most influence on the ETo estimation. For the period 2006–2015, the comparison between air temperature, global solar radiation, wind speed, and relative air humidity, measured from 39 ground weather stations in Sicily, and ERA5-Land was carried out and then, through FAO56-PM equation daily ETo values were estimated using both databases. The statistical indicators Root Mean Square Error (RMSE) and Mean Bias Error (MBE) confirm the possibility of considering the ERA5-Land a suitable solution to estimate ETo. The sensitivity analysis showed that good ETo estimation depends mainly on the accuracy of the relative air humidity and air temperature data.

The latest version of CENDL database, CENDL-3.2, was released in 2020 with the significant changes in 56Fe nuclear data compared with ENDF/B-Ⅷ.0, the latest version of ENDF/B. In order to determine the effect of the changes on the effective multiplication factors, thirty-eight criticality benchmarks were selected for validation and analysis, including twenty-five highly enriched models, eight plutonium mental models and five other models. Then, thirty-eight criticality benchmarks were modeled in Monte Carlo program and calculated with complete ENDF/B-Ⅷ.0, and with hybrid ENDF/B-Ⅷ.0 with CENDL-3.2 56Fe nuclear data substituted, respectively. The calculation results of the effective multiplication factors show that the relative biases of CENDL-3.2 are within range of -1 046-1 955 pcm and the difference of relative biases between CENDL-3.2 and ENDF/B-Ⅷ.0 is within range of -381-290 pcm. And the relative biases of CENDL-3.2 and ENDF/B-Ⅷ.0 are basically within three standard deviations. Furthermore, the effective multiplication factors of ENDF/B-Ⅷ.0 are closer to the benchmark values for highly enriched uranium models and plutonium mental models. The effective multiplication factors of ENDF/B-Ⅷ.0 have better consistency for highly enriched models, and the effective multiplication factors of CENDL-3.2 have better consistency for plutonium mental models. Apart from this, the calculation results of main cross section sensitivity coefficients show that five of the thirty-eight models are not iron sensitive and the effective multiplication factors are primarily influenced by the 56Fe elastic scattering cross section, inelastic scattering cross section and radiative capture cross section. If the increment of the effective multiplication factors produced by the change of the elastic scattering cross section is larger than the decrease produced by the change of the inelastic scattering cross section and the radiative capture cross section, absolute bias is positive. Otherwise, absolute bias is negative.

We present a stochastic time-delay susceptible-exposed-asymptomatic-symptom-vaccinated-recovered (SEAQVR) model with media publicity effect in this study. The model takes into account the impacts of noise, time delay and public sensitivity on infectious illness propagation. The stochastic dynamics of the system are analyzed at the Hopf bifurcation, using time delay and noise intensity as bifurcation parameters, and the theoretical conclusions are validated using numerical simulation. Increasing the time delay and sensitivity coefficient can effectively delay the occurrence of the peak number of infected individuals and mitigate the extent of infection. Additionally, time delay and noise intensity are shown to have specific thresholds, beyond which periodic infections occur. Notably, heightened public sensitivity reduces the threshold for time delay, and media publicity directly affects public sensitivity. The numerical simulation reveals that increasing media publicity intensity does not always yield better results, and that the sensitivity of the public at present is an important reference index for setting an appropriate publicity intensity.

Higher temperatures are expected to increase evaporation and reference evapotranspiration (ETo). However, a decrease in ETo has been observed in numerous regions worldwide. ETo is controlled by climate variables besides temperature; wind speed, air humidity, and radiation, which vary according to regional climatic conditions, may also be drivers. Few studies have quantified the sensitivity and contributions of climate variables to ETo change in tropical savanna climates. Long‐term (1991–2019) climate time series in northern Thailand was used to assess the trends in ETo and determine which climate variables exert the strongest control on ETo, during the rainy and non‐rainy season, as an example for the tropical savanna climate. Furthermore, this study used the proportion of contribution and sum of positive (negative) contribution and classified the results into five groups to analyse the change in ETo. This helped to determine the climate variable with the highest contribution. From this study, ETo was the most sensitive to the maximum temperature, followed by sunshine duration in both rainy and non‐rainy seasons. Furthermore, the variables that contributed the most to the long‐term change in ETo were sunshine duration and wind speed. The increase (decrease) in sunshine duration and wind speed contributed to the increase (decrease) in ETo in this area. Understanding ETo changes and determining whether ETo has a strong tendency to change are the basis for water resource planning and management in the region. [ABSTRACT FROM AUTHOR]

In this study, the coupling and the relative sensitivity characteristics of a Dual-Core photonic crystal fiber (DC-PCF)-based liquid sensor are evaluated by employing the full-vectorial finite element method (FV-FEM). The simulation results demonstrate that coupling length of the proposed sensor varies between 2 mm and 0.2 mm length at wide wavelength range (800–1600 nm) for low index analytes (1.33–1.36). Besides, birefringence of order ≈ 1 0 − 4 is reported. It is found that analyte with 1.36 index reaches higher sensitivity levels. On the other hand, the coupling length of the proposed sensor can be optimized with the ellipticity ratio of the central core hole. Bending analysis on coupling length and optical power fluctuations is also reported. It is found that the power flow in one core is increasing almost 90% towards the bending direction. The proposed structure with simple design parameters has a great potential in various biomedical applications including DNA detection and can also be employed as fiber-based refractometer in various sensing applications. [ABSTRACT FROM AUTHOR]

A one-component strain gauge dynamometer with a force measurement range of 0–0.33 N was developed and manufactured at the N. E. Zhukovsky Central Aerohydrodynamic Institute, to measure the unsteady friction force of the boundary layer on the wind tunnel walls at remarkably high Reynolds numbers. The static and dynamic characteristics of the dynamometer and its systematic errors were also investigated. The effects of the temperature, longitudinal, normal, and lateral forces, as well as the position of the longitudinal force application, were analyzed during the calibration. A block was designed and manufactured to calibrate the dynamometer using dead weights in a wind tunnel. Special experiments were performed in laboratory conditions to determine the friction force acting on the block axis. The developed dynamometer represents a dynamic system with its natural frequency of oscillations. The correction for the dynamics of the dynamometer is suggested on the basis of the method developed earlier. The mass of the metric part of the dynamometer, its natural oscillation frequency in the absence of damping in the direction of measuring the friction force, and the damping coefficient were determined to calculate the correction. The correction is verified by experiment with the application of a stepwise force. The effect of static and dynamic temperature components (the influence of the average temperature value and its change over time, respectively) on dynamometer readings was investigated. Corrections are proposed to eliminate the systematic errors due to the effect of temperature based on the previously developed method. Results revealed that the lateral force does not affect the dynamometer readings, while the effect of the normal force is 1.1% of the sensitivity coefficient of the longitudinal force. The temperature sensitivity of the sensitivity coefficient of the dynamometer is 0.017%/°C. The total measurement uncertainty of the friction force dynamometer was estimated as the standard deviation of the measurement results from the average value not exceeding 0.076% of the measurement range, and the relative uncertainty of the sensitivity coefficient is not more than 0.03%. The measurement uncertainty of the unsteady friction force will not exceed 0.86% of the dynamometer range with natural oscillations of the sensitive element. The developed single-component strain gauge dynamometer can be used to determine the friction coefficient of the boundary layer on a flat surface. [ABSTRACT FROM AUTHOR]

Dry-wet variations are a hot topic in global climate change research. Climate warming has led to the changes of evapotranspiration and precipitation are unevenly distributed, which have and will undoubtedly affect the dry-wet variations. In this study, based on daily climatic data from 423 meteorological stations in Southwest China (SWC), we analyze the trends and spatial variabilities of dry-wet climatic factors during 1961–2017, such as potential evapotranspiration (ET0), precipitation, and humid index (HI). Also, we investigate the possible influencing factors causing dry-wet variations. The results show that the arid, semi-arid, and humid regions decreased in 1991–2017 compared with those in 1961–1990, but the sub-humid regions increased. During 1961–2017, there was a noticeable decreasing trend in precipitation, while the variation trend in the ET0 was not apparent, which contributed to the dry climate in the SWC. The ET0 was most sensitive to temperature, followed by relative humidity. The contribution to the change of the ET0 was most remarkable for the change of temperature, followed by sunshine hours and wind speed. On the seasonal scale, the climate became drier in summer and autumn during 1961–2017, but there were no obvious wet-dry variations in spring and winter. Temperature and wind speed were the major factors causing the ET0 variation in spring and winter. Temperature, wind speed, and relative humidity were the critical factors contributing to the ET0 variation in autumn. while sunshine hours played a primary role in the ET0 variation in summer. On the monthly scale, the climate tended to be dry in most months, except for January, March, June, and July. Temperature was the most prominent contributor to the ET0 increase in most months. Also, wind speed and sunshine hours were the main factors of the ET0 reduction in October–May and June–September, respectively. This study can provide a specific reference for drought monitoring and early warning in different climate zones of the SWC. [ABSTRACT FROM AUTHOR]

Making management decisions for the quantitative and qualitative improvement of product production effectively begins with selecting the correct and appropriate set of physical and hydraulic characteristics in the form of a soil physical quality index. In order to investigate the physical quality of Shabaster Plain which were under wheat cultivation and to determine the role of the number and type of properties on the quality of the soils, 94 soils from these lands until the year 2022, were selected. To determine the soil physical quality index (SPQI), the minimum data set (MDS) was used by principal component analysis (PCA). 13 physical, chemical, and hydraulic properties (clay, silt, bulk density, aggregate size distribution, electrical conductivity, sodium adsorption ratio, pH, organic carbon, hydraulic conductivity (K_s), conventional plant available water (CPAW), integral energy (EI), dexter index (S_dex), Kirchhoff potential (M_h0)) were consciously entered into four stages in the principal component analysis so that the output is not only the minimum data set but also the best data set. EC appeared as one of the main components in all arrays. The first array was eliminated from the minimum data set. Comparing the mean soil physical quality index between the arrays with Duncan's test showed a significant difference at the 99% probability level (p<0.01) between the fourth array and the second and third arrays. The high sensitivity coefficient of the fourth array (9.78) with the second and third arrays (5.43) showed that the correct addition of the Kirchhoff potential to the data set, led to different results in terms of classifying soil physical quality. As a result, the quality of the soils decreased from 72% of very suitable and suitable soils and 28% of the soils with severe and very severe restrictions in the second and third arrays to 41% of very suitable and suitable soils and 59% of soils with restrictions in the fourth array. This data demonstrates using easily measured properties, to simplify the soil quality assessment system, does not always produce accurate results. [ABSTRACT FROM AUTHOR]

In the unstable conditions of development of the world economy, which occur under the influence of factors of political and economic instability, one of the most important problems of stable functioning and development of the country’s economy is to ensure the stable development of both the kinds of economic activities and enterprises. Since all kinds of economic activity react differently to the instability of the external environment, it is important to analyze the conditions of functioning and the results of the activities of enterprises by the kinds in order to form adequate and adaptive managerial reactions to the tactical and strategic behavior of the latter. The aim of the article is to study and determine the sensitivity of kinds of economic activities to changes in the external environment in order to form adaptive economic behavior of enterprises. In order to achieve this goal, in the course of the research the following scientific methods were used: comparative analysis, graphic analysis, structural-dynamic analysis, coefficient and cluster analysis. The article proposes an algorithmic model of formation of economic behavior of enterprise depending on the level of sensitivity of the certain kind of economic activity. Implementation of the proposed model will allow to form an effective system of managerial decisions on the future behavior of enterprises. The basis for the development of managerial decisions is the analysis of tendencies in the development of kinds of economic activity of the country by the indicator of gross value added, the allocation of cluster groups of kinds of economic activity by the level of their sensitivity. All this will allow to form an effective system of managerial decision-making, which is aimed at maintaining a sustainable attractor of economic development of the enterprise. [ABSTRACT FROM AUTHOR]

Model updating is the process of calibrating model parameters to improve the accuracy of numerical prediction. To improve the accuracy and efficiency of model updating, this paper proposes a model updating method based on Bayesian theory and improved objective function. A natural frequency damage index is proposed based on the Bayesian theory, which is calculated according to the established damage position function and the measured frequency data. The distribution of the index can determine the damage location and the number of updated parameters for model updating. An objective function with weight terms is proposed based on strain assurance criterion to describes the difference between the finite element model and the actual structure, and the weight term of the objective function is determined by the sensitivity coefficient. Examples show that the improved model updating method is more accurate and efficient. [ABSTRACT FROM AUTHOR]

Based on the daily meteorological data of 710 stations from 1970 to 2017, authors apply the Mann-Kendall test method and contribution analysis method, analyze the variation characteristics of annual ETo (potential evapotranspiration) and its sensitive factors, further quantify the contribution of meteorological factors to ETo variation in different climate regions. The results showed that, (1) among 710 meteorological stations, 177 stations showed a significant increase trend (0.51 to 5.55mm·y−1, P<0.05), 147 stations showed a significant decrease trend (−0.65 to −5.00mm·y−1, P<0.05), and 386 stations showed no-significant change trend. T and U showed an increasing trend, while RH and RN showed a decreasing trend in different climate regions. (2) The sensitivity factors of ETo to meteorological variables were differ in climate regions, in extreme arid region, arid region and semi-arid region ETo was most sensitive to net radiation(RN), and most sensitive factor change to relative humidity(RH) in the semi-humid region and humid region, also the sensitivity of ETo to RH and RN increased with the increase of humidity. (3) The change trend of ETo was influenced by the sensitivity of climate factors and the relative rate of change. The rise of ETo in extreme arid region, arid region, semi-arid region and semi-humid region were mainly caused by the increase of T, while the decrease of ETo was mainly caused by the decrease of U, the change of ETo in humid region was caused by its high sensitivity to RH and RN. In summary, compared with the sensitivity coefficient, the contribution index considering the relative rate of change is more indicative of the influence of climate factors on ETo change. This study is conducive to for scientific understanding of regional climate change and hydrological cycle response mechanism. [ABSTRACT FROM AUTHOR]

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the principle of FBG sensing and classical mechanics model of acceleration,the fundamental frequency and acceleration sensitivity coefficient of the fiber Bragg grating (FBG) acceleration sensor are theoretically analyzed in this study. An equal strength cantilever beam-based FBG acceleration sensor was designed based on the vibration frequency of conventional bridges and carried out experimental research. The results show that the fundamental frequency of the sensor increases when the cantilever beam thickness increases, while the sensitivity coefficient decreases. However, when the block mass increased, the fundamental frequency decreased in contrast to an elevated sensitivity coefficient. The experimental findings were found to be in line with the theoretical hypothesis. The sensors had good signal response performance and anti-transverse interference performance. In order to solve the problem of low sensitivity coefficient of sensor, the sensor was optimized and tested following the plane section assumption principle of classical mechanics. The result shows that the fundamental frequency of the optimized sensor remains unchanged, the sensitivity coefficient is increased by 2.6 times. The research provided an FBG acceleration sensor with suitable fundamental frequency, high sensitivity and other excellent performance for bridge monitoring. [ABSTRACT FROM AUTHOR]

Six kinds of flexible strain sensors were prepared by carbonizing cotton and viscose knitted fabrics into conductive materials and then compounding them with thermoplastic urethane film, to systematically investigate the sensing properties of flexible strain sensors for carbonized knitted fabrics. The influences of tensile direction, fiber material, carbonized fabric structure and density on the sensitivity coefficient and repeatability of the sensors were investigated by tensile test. The results indicate that the sensing properties of the sensors in the course direction is better than that in the wale direction. The sensing properties of the strain sensor made of cotton is superior to that made of viscose. The comprehensive sensing properties of cotton plain knitted fabric strain sensor are the best, followed by 1x1 rib fabric, and interlock fabric is the worst. The smaller the fabric density, the better the sensing properties of the sensor. The research has guiding significance for the design of strain sensor. [ABSTRACT FROM AUTHOR]

In order to study the influence mechanism of effective stress on permeability, the coal permeability test experiment under simultaneous loading of axial and confining pressure was carried out using the self-developed coal-rock gas adsorption-desorption-seepage platform. The mean effective stress parameter is introduced to characterize the loaded state of the coal body. At the same time, in order to eliminate the influence of the individual differences of the specimens, the effective stress sensitivity coefficient is defined, and the control mechanism and variation law of the effective stress on the permeability of the coal body are discussed in depth. The results show that when the gas pressure remains constant, the coal permeability decreases gradually with the increase of the effective stress, and its variation law conforms to the negative exponential relationship. With the increase of effective stress, the sensitivity coefficient gradually decreases, and it conforms to the power function relationship. At the same time, a mathematical model of coal sample permeability and effective stress is constructed based on the sensitivity coefficient.

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Reference evapotranspiration is a vital research item for hydrologic pattern systems in drought-flood risks of a country like Bangladesh. The present research examines spatiotemporal fluctuations in reference evapotranspiration and influencing factors of these fluctuations by applying the Mann–Kendall test with the Theil–Sen's estimator, Inverse Distance Weighted interpolation method, differential equation and detrending method depending on diurnal meteorological data sets attained from 25 weather observatories between 1981 and 2018. By current research, the FAO 56 Penman–Monteith (PM) model is executed for determining seasonal and annual reference evapotranspiration (ET ), and differential equation and detrending method is implemented for assessing correlation, sensitivities, and benefaction of four climatological variables to ET . The MK trend analysis has been performed jointly with the Theil–Sen's estimator to discover movement of ET and meteorological variables. ET displayed a conspicuous descendant tendency () at post-monsoon (–0.87 mm/year), winter (–1.13 mm/year), and annual time scale (–3.31 mm/year) in whole Bangladesh, but at the same period, a non-significant descending tendency of ET was observed in pre-monsoon (–1.47 mm/year) and monsoon (–0.07 mm/year) season in the study area. These changes of ET could be explained by a notable rising tendency in average temperature (TA) and actual vapor pressure (VP) and noteworthy declining tendencies in wind speed (WS) and sunshine duration (SD). ET had been maximum sensitive to TA, a bit less, to VP, SD, and WS in the annual and seasonal periods. TA, WS, and SD produced a positive effect, whereas the VP negatively affected seasonal and annual ET . Despite the negative effect on ET , VP was the second most sensitive to the annual and all seasonal ET after TA. Crosswise the entire study area, WS had the greatest influence to ET , after that TA and SD. At the same time, the positive contribution of VP to ET could not counterbalance the negative contributions of WS, TA, and SD. While the consequence of VP on variations in ET is minor, it has to be considered particularly in the cold period. The counter association among inclining TA and declining ET , which is known as the "evaporation paradox," happenned in Bangladesh. These research outcomes will be beneficial to develop forthcoming water scheduling and regulation of feasible water resources to lessen climate change effects on agronomic water prerequisites and regulate human induced actions. [ABSTRACT FROM AUTHOR]

With global climate change and increasingly extreme weather conditions, the water quality of the Lijiang River Basin (LRB) is facing huge threats. At present, there is still a lack of systematic research on water quality indicators and the influence of indirect factors such as meteorological factors on it in the LRB. Therefore, this study is based on the meteorological, hydrological, and water quality data of the LRB from 2012 to 2018, using the Mann–Kendall test, Morlet wavelet method, Spearman's rank correlation coefficient, sensitivity, and contribution rate to quantitative analysis of the relationship between climate conditions and water quality indicators. The results show that the change trends of these hydrological and climatic conditions have almost no significant sudden change; precipitation and streamflow are decreasing each year; the streamflow trend exhibits time hysteresis; precipitation has a stronger influence downstream than on the local area; water quality indicators of both stations exhibited a change period of around 18 to 20 months, with the exception of pH. Water quality indicators are insensitive to precipitation and streamflow, and sensitive to humidity and wind speed; DO was negatively correlated with climate indicators apart from wind speed; almost all water quality indicators in Yangshuo are highly sensitive to air temperature, and the contribution rate of air temperature to ORP and TP reached 4.81% and 3.56%, respectively; sunshine duration has a positive impact on reducing NH4-N and TP. The difference between Yangshuo and Guilin is mostly due to the input of external sources on both sides of the Lijiang River, which results in variations in climate conditions sensitivities. [ABSTRACT FROM AUTHOR]

This paper investigates the instability characteristics of CO/H2/air and CH4/H2/air mixtures in a narrow channel under standard temperature and pressure conditions. The CO/H2 mixture exhibits a greater overpressure growth rate and maximum explosion overpressure as compared to the CH4/H2 mixture at the same hydrogen content. As the hydrogen content increases, the maximum explosion overpressure (Pmax) value increases, while the corresponding time (θ) value gradually decreases. The maximum explosion overpressure of CH4/H2 and CO/H2 mixtures is 28.27 kPa and 25.09 kPa, respectively. The flame wrinkles to form cells due to the Darius-Landau instability, and the interaction between the vortex tube and premixed flame affects the structure of turbulent premixed combustion. The oscillation frequency of the overpressure increases with increasing hydrogen content, and the oscillation belongs to the Helmholtz oscillation. The CO/H2 mixtures exhibit greater flame thickness than CH4/H2 mixtures, resulting in lower Peclet numbers and therefore greater relative importance of heat losses. As the hydrogen content increases, the sensitivity coefficient of R99 (OH + CO <=> H + CO2) in the CO/H2 mixture gradually decreases, while the sensitivity coefficients of R38 (H + O2 <=> O + OH) and R84 (OH + H2 <=> H + H2O) increase. The elementary reaction R38 plays a leading role in increasing the laminar burning velocity of the CH4/H2 mixture. The trend of R38 variation in the two mixtures is opposite with increasing hydrogen content. [ABSTRACT FROM AUTHOR]

Accurate forecast of spare parts demand is of great significance for modern enterprises to provide accurate support and improve market competitiveness. In most studies, mathematical laws are used to forecast, without enough consideration of the actual operation of equipment and the fact that the accuracy of spare parts demand forecasting is not high, which cannot adapt to the new characteristics of complex equipment use environment and fierce market competition in modern enterprises. The digital twin model can be used to forecast the demand for spare parts more accurately and guide modern enterprises to carry out accurate support. By analyzing the current spare parts demand of modern enterprises, the paper puts forward the forecasting ideas of spare parts demand based on the digital twin model by using the digital twin model of equipment maintenance management in modern enterprises. In the digital twin model, the theoretical demand forecasting model of spare parts based on life distribution of replaceable units is introduced, and the sensitivity coefficient system of spare parts demand of replaceable units to operation and environment is constructed. The digital twin model is used to feedback train the sensitivity coefficient to obtain the reliable spare parts demand rules. Based on the theoretical demand and sensitivity coefficient of spare parts, the forecasting method of spare parts demand is given, and the spare parts demand forecasting model is established. Through case analysis, the feasibility and accuracy of the forecasting model are verified. [ABSTRACT FROM AUTHOR]

• Differences in criteria weights were significant between expert groups. • Rankings varied considerably across different MCDM methods. • Sensitivity analysis identified transit connectivity as the most critical criterion. • Validation with smart card data highlighted the robustness of certain MCDM methods. A key challenge for transport managers and planners in sustainable development is evaluating transit facilities' performance. While Multi-Criteria Decision-Making (MCDM) tools are often used, they can be influenced by experts' subjective biases. This study applies MCDM to assess Mass Rapid Transit (MRT) stations in Jakarta, Indonesia, focusing on Transit-Oriented Development (TOD). The primary goal is to compare stakeholder perspectives and MCDM methods, complemented by a sensitivity analysis and validation with real-world smart card data. The findings reveal significant differences in criteria weighting between Indonesian and non-Indonesian experts, and between academic and non-academic experts, especially in transit connectivity and land use diversity. The study also shows variations in station rankings across different MCDM methods. Sensitivity analysis identifies transit connectivity as the most critical criterion. Simple Additive Weighting (SAW) with linear normalisation aligns well with actual usage data and shows robustness in sensitivity analysis, making it the most reliable method for TOD evaluation. The study highlights the need for continuous TOD performance monitoring and the regular collection of real-world data on ridership and TOD indicators. [ABSTRACT FROM AUTHOR]

• The current progress of the online power-distribution reconstruction code based on POD is presented. • POD samples are compressed based on the similarity of power-distributions. • The applicability of the code to detector reduction is explored. • The sensitivity coefficients of detectors are calculated to estimate the importance of detector measurements. In this study, the current progress of the online power-distribution reconstruction code CORN is presented, which employs the proper orthogonal decomposition (POD) method. The adopted strategy for constructing the POD sample space relies on capitalizing on the similarity of power-distributions to preserve spatial traits while diminishing the count of POD bases required. The efficacy of the online power-distribution reconstruction code has been demonstrated on five operational states of the BEAVRS benchmark core, exhibiting maximum reconstruction deviations under 2.5%. Furthermore, the study explores the applicability of the method to the reduction of the quantity of detectors. The sensitivity coefficients of detectors are calculated to help estimate the importance of detector measurements. Then the detector reduction test is carried out. Numerical results show methods and model presented in this paper have relatively good applicability to the reduction of the quantity of detectors. [ABSTRACT FROM AUTHOR]

Processing of aquifer test drawdowns to obtain estimates of transmissivity, and sometimes storativity, is an integral part of hydrogeological site investigations. Analysis of these data often relies on an assumption of hydraulic property uniformity. Aquifer properties are often estimated by fitting a Theis curve to measured drawdowns. Where an aquifer exhibits heterogeneity, quantities that are forthcoming from such analyses are assumed to represent spatially-averaged properties. However the nature of the averaging process, and the area over which averaging takes place are unknown. In this study we derive spatial averaging functions that link inferred hydraulic properties to real-world hydraulic properties. These functions employ Fréchet integrals derived by previous investigators that link observation well drawdowns to aquifer properties under an assumption of mild aquifer heterogeneity. It is shown that these hydraulic property spatial averaging functions are complex, especially at times that immediately follow the commencement of pumping. Furthermore, they cross hydraulic property boundaries, so that estimates of storativity can be contaminated by heterogeneities in real-world transmissivity, and vice versa. Because of its greater averaging area at later times, estimates of transmissivity are generally more immune to the effects of local hydraulic property heterogeneity than are those of storativity. They are therefore more reflective of broadscale real-world hydraulic properties, particularly those that prevail in areas that are removed from the immediate vicinity of the pumping and observation wells.

Owing to the promotion of DME (dimethyl ether) liquefaction transportation technology and in-station hydrogen production technology, the explosion risk of DME/H2 blended gas caused by unintended or uncontrollable leakage has become the focus of attention. To assess the explosion risk, the explosion dynamics and chain mechanism of DME/H2 blended gas at typical fuel-lean/rich concentrations were investigated with experiments and numerical simulations. The results show that the maximum explosion overpressure Pmax increases and then decreases with increasing equivalence ratio for Φ = 0.6–2.0, and Pmax is maximal for Φ = 1.0 (the maximum increase is 20.3%). In the zone away 2.85 m from the ignition point, the effect of fuel-rich concentrations on flame temperature lift and explosion risk enhancement gradually emerges, which is because that the fuel concentration here is diluted to near stoichiometric concentration. The fuel-rich concentration caused a secondary flame acceleration and further flame propagation in the outfield zone, and the flame propagation distance is increased by 22.6% compared to the fuel-lean concentration. The high temperature caused by the incorporation of hydrogen makes the pyrolysis reaction CH3OCH3(+M)CH3O + CH3(+M) promotes the explosion most effectively. The sensitivity coefficients of most elementary reactions reach maximum at the stoichiometric concentration, thereby promoting or inhibiting explosions most effectively. At Φ = 1.0–1.1, the equilibrium molar fractions of H and OH radicals are maximal, the chemical reactivity gets highest, and the explosion risk is greatest.

We propose the use of reduced-order modeling to improve the sensitivity coefficient evaluation method based on Lasso-type penalized linear regression. In this method, cross sections of interest are uniformly randomly sampled, and corresponding perturbed core analyses are performed. The sensitivity coefficients of the higher-dimensional model are expanded by the active subspace (AS) attained by the lower-dimensional model, and the expansion coefficients are estimated by the Lasso regression. In addition, AS bases can be flexibly chosen according to neutronics parameters of interest. We conducted a verification calculation for an accelerator-driven system and clarified that the proposed method successfully reduces the calculation cost by a couple of orders of magnitude compared with the direct method. The proposed method can be used to practically evaluate the sensitivity coefficients of various parameters. [ABSTRACT FROM AUTHOR]

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper develops the conceptual design and error analysis of a cable-driven parallel robot (CDPR). The earlier error analysis of CDPRs generally regarded the cable around the pulley as a center point and neglected the radius of the pulleys. In this paper, the conceptual design of a CDPR with pulleys on its base platform is performed, and an error mapping model considering the influence of radius of the pulleys for the CDPR is established through kinematics analysis and a full matrix complete differential method. Monte Carlo simulation is adopted to deal with the sensitivity analysis, which can directly describe the contribution of each error component to the total orientation error of the CDPR by virtue of the error modeling. The results show that the sensitivity coefficients of pulleys' geometric errors and geometric errors of the cables are relatively larger, which confirms that the cable length errors and pulleys' geometric errors should be given higher priority in design and processing. [ABSTRACT FROM AUTHOR]

Keywords: fucoxanthin; kinetic model; microalgae; sensitivity coefficient EN fucoxanthin kinetic model microalgae sensitivity coefficient 723 734 12 07/21/22 20220701 NES 220701 1 Introduction As a kind of marine natural active product with development value, fucoxanthin production has been widely concerned and studied in recent years ([18]). In other words, the decrease of microalgal growth has much greater impact on HT ht than HT ht . The performance of the parameter estimation problem is defined as HT ht Graph (12)where the subscripts I l i , I i i , I j i are respectively the indexes of the group of experiments, the substances and the measured time points. However, the decrease of HT ht is not as fast as that of HT ht . [Extracted from the article]

The calculation of neutron activation source terms is an essential task in the radiation of nuclear reactors, and its sensitivity and uncertainty (S&U) analysis can help better identify and control the influencing factors and safety margin of activation source terms. In this paper, we studied the statistical sampling strategies for the S&U analysis of activation source terms, established the calculation process of sensitivity coefficient and uncertainty, and the S&U analysis module based on sampling methods was integrated for the proprietary developed activation computation program ABURN. Two sampling ways, Monte Carlo and Latin hypercube sampling treatments, were employed to figure out the cases of pure decay single chain, pure activation single chain, and complex reaction network. The sensitivity coefficients and uncertainty of nuclide inventory were evaluated by taking the uncertainty of decay constant or reaction cross-section into account. The simulation results indicate that after introducing the LHS sampling method, the activation calculation program ABURN can improve computational efficiency in sensitivity and uncertainty analysis. Subsequent results demonstrated that the sensitivity coefficients and uncertainty solutions based on the sampling methods in the ABURN program were in good agreement with the analytical solutions and the FISPACT program, which verified the accuracy of the approaches and program in this paper. • S&U analysis process utilizing the sampling methods is conducted for the nuclide activation calculation. • Sample precision and sampling efficiency are advanced by adopting the Latin hypercube sampling treatment. • S&U calculation module is developed and integrated into the neutron activation calculation program ABURN. • Accuracy of the computation procedure is verified through benchmark example studies. [ABSTRACT FROM AUTHOR]

Understanding the impact of changes in climatic variables on reference evapotranspiration (ETo) is important for predicting possible implications of climate change on the overall hydrology of an area. This study aimed to determine the effects of changes in ETo with respect to changes in climatic variables. In addition, the specific objective was to determine the sensitivity coefficients of ETo in seven different locations in Nigeria with distinct agroecology, namely Maiduguri (Sahel savannah), Sokoto (Sudan savannah), Kaduna (Guinea savannah), Jos (Montane), Enugu (Derived Savannah), Ibadan (tropical rainforest), and Port Harcourt (coastal). The results showed that ETo is most sensitive to changes in maximum temperature (Tmax) in Maiduguri, Sokoto, Kaduna, and Jos. In Enugu and Ibadan, ETo is most sensitive to changes in solar radiation (Rs), while in Port Harcourt, ETo is most sensitive to relative humidity (RH). Overall, based on the average annual sensitivity coefficients (SCs) of the study area, the SC is ranked in the order: RH > Rs > Tmax > U2 > Tmin. Also, the results showed positive SCs of ETo to Rs, Tmax, U2, Tmin, and negative SC for RH. This study can serve as a baseline for sustainable water management in the context of climate change and adapted to areas with a similar climate. HIGHLIGHTS For the first time, the influence of climatic variables on reference evapotranspiration (ETo) was evaluated under different agro-ecological zones in Nigeria.; For all locations in northern Nigeria, ETo is most and least sensitive to maximum temperature (Tmax) and minimum temperature (Tmin), respectively, while in southern Nigeria, ETo is sensitive to solar radiation (Rs) and relative humidity (RH) and least sensitive to wind speed (U2).; During the growing season, ETo is most sensitive to RH and Rs across all study locations.; Across all agro-ecological zones, Rs, Tmax, Tmin, and U2 had positive sensitivity coefficients (SCs), while RH had a negative SC.; This study can serve as a baseline for sustainable water management in the context of climate change and adapted to areas with a similar climate.;

• An improved non-destructive magnetic-based steel bar corrosion detection with simple structure and high accuracy. • Equivalent numerical model to quantify the corrosion degrees and impacts of frame internal structural parameters. • Sensitivity coefficient changes linearly with the diameter of steel rods. • Increase in frame width and foot length are beneficial to growth of sensitivity coefficient. • Adding extra calibration magnetic circuits leads to reduction in sensitivity coefficient. Steel-bar corrosion can not only induce corrosion cracking, but also cause the bearing capacity decline of concrete structures. This contribution reported an improved magnetic-based steel bar corrosion detection apparatus with simple structure and high accuracy. Accelerated corrosion tests on steel rebar were carried out to calibrate the accuracy of the magnetic-based corrosion detection apparatus. A parameter of sensitivity coefficient, k , was proposed to evaluate the corrosion detection sensitivity of the apparatus. An equivalent numerical model was established based on multi-physical simulation to quantify the corrosion degrees and explore the impacts of the frame internal structural parameters. Results show that k is stable and changes linearly with the diameter of steel rods tested. Increasing frame width and foot length can increase k , and adding extra calibration magnetic circuits leads to reduction in k. Overall, the modified magnetic-based apparatus provides a simple, reliable, accurate and non-destructive method for steel corrosion detection. [ABSTRACT FROM AUTHOR]

Based on the environmental characteristics near underwater explosion source, an underwater explosion pressure sensor with PVDF film as the sensitive unit is proposed in this paper. The effect of temperature on the sensitivity coefficient of the sensitive unit was tested with the SHPB test system. By combining with numerical simulation and experiment, the measurement accuracy and reliability of the sensor near the explosion source are verified. The results show that the peak pressure and temperature of a 1 kg emulsion explosive explosion at one times the charge diameter are approximately 1.753 GPa and 317 K. In the temperature range of 5∼50 °C, the temperature has little influence on the sensitivity coefficient (k = 84 pc/MPa). In the temperature range of 50∼80 °C, the sensitivity coefficient of PVDF film increases with the increase of temperature, and the relationship between temperature and sensitivity coefficient is obtained by fitting the exponential function. The time history curves of pressure obtained by the high-frequency pressure sensor and the self-made PVDF pressure sensor are basically consistent, and the pressure peak values are within a reasonable range. Meanwhile, the measurement error of the PVDF pressure sensor and the PCB pressure sensor is less than 1 MPa, which verifies the measurement reliability of the PVDF pressure sensor. The peak pressures of 2 kg of emulsion explosive at 0.2 m and 0.4 m are 323.42 MPa and 173.86 MPa, respectively, and the errors with the numerical simulation results are about 19 MPa and 9 MPa, respectively. Meanwhile, the time-history curves of the complete pressure of 10 kg of emulsion explosive at the position of 0.3 m and the energy of the specific shock wave of 0.7 MJ/kg have been obtained, which verifies the feasibility of measuring the sensor in the vicinity of the explosion source. • Influence of temperature on the sensitivity coefficient of the sensitive unit is shown. • Pressure of 1 kg emulsion explosive reaches 1.7 GPa and the peak temperature reaches 317K at the position of 1 times the charge diameter. • In the temperature range of 2∼50 °C, the temperature has little influence on the sensitivity coefficient, and K = 84pc/MPa. • In the temperature range of 50∼80 °C, the sensitivity coefficient of PVDF film increases with the increase of temperature. • Measurement error of the PVDF pressure sensor and the PCB pressure sensor is less than 1 MPa. • Pressure peak of 2 kg emulsion explosive at the positions of 0.2m and 0.4m underwater explosion are 323 MPa and 174 MPa. • Time history curve of complete pressure and specific shock wave energy of 0.71 MJ/kg at the position of 0.3m for 10 kg emulsion explosive was obtained. [ABSTRACT FROM AUTHOR]

Reference evapotranspiration (ET0) is essential for agricultural production and crop water management. The recent climate change affecting the spatiotemporal variation of ET0 in eastern China continues to still be less understood. For this purpose, the latest observed data from 77 meteorological stations in Anhui province were utilized to determine the spatiotemporal variations of ET0 by the use of the Penman–Monteith FAO 56 (PMF-56) model. Furthermore, the Theil–Sen estimator and the Mann–Kendall (M–K) test were adopted to analyze the trends of ET0 and meteorological factors. Moreover, the differential method was employed to explore the sensitivity of ET0 to meteorological factors and the contributions of meteorological factors to ET0 trends. Results show that the ET0 decreased significantly before 1990, and then increased slowly. The ET0 is commonly higher in the north and lower in the south. ET0 is most sensitive to relative humidity (RH), except in summer. However, in summer, net radiation (Rn) is the most sensitive factor. During 1961–1990, Rn was the leading factor annually, during the growing season and summer, while wind speed (u2) played a leading role in others. All meteorological factors provide negative contributions to ET0 trends, which ultimately lead to decreasing ET0 trends. During 1991–2019, the leading factor of ET0 trends changed to the mean temperature (Ta) annually, during the growing season, spring and summer, and then to Rn in others. Overall, the negative contributions from u2 and Rn cannot offset the positive contributions from Ta and RH, which ultimately lead to slow upward ET0 trends. The dramatic drop in the amount of u2 that contributes to the changes in ET0 in Region III is also worth noting. [ABSTRACT FROM AUTHOR]

The expansion of rubber (Hevea brasiliensis) cultivation plantation over the past few decades has been significantly explosive in Xishuangbanna, southwest China. More and more evidences concerning the expansion of rubber plantations lead to the negative influence to local regional hydrology. It is vital to explore the impact of climate change and rubber (Hevea brasiliensis) plantation expansion on reference evapotranspiration (ET0) for the sustainable and efficient use of regional water resources. In this study, the spatiotemporal variation of ET0 as well as its relationship in rubber plantations area in Xishuangbanna from 1970–2017 were analyzed by using trend, correlation and contribution analysis. The results showed that the rubber plantation was 12,768 ha yr–1 from 1990 to 2017 in Xishuangbanna, and nearly 40.8% of new rubber plantations expanded above 900 m in altitude from 2000 to 2017. Sunshine duration and average relative humidity were the key meteorological factors that affect ET0 in Xishuangbanna, with the sensitivity coefficient of 0.51 and 0.35, respectively. The multiyear relative change of ET0 in Xishuangbanna was 9.18%, and the total contribution of major climate factors was 7.87% during 1970 and 2017. The average relative humidity in the plantation area decreases, which directly leads to the increase of ET0. The amount of ET0 change from 2000 to 2017 affected by climate change increased at 3.13 mm/10a, whereas it was 2.17 mm/10a affected by the expansion of rubber plantations by quantitative separation. ET0 was significantly affected by climate change but intensified by the expansion of rubber plantation. [ABSTRACT FROM AUTHOR]

The expansion of rubber (Hevea brasiliensis) cultivation plantation over the past few decades has been significantly explosive in Xishuangbanna, southwest China. More and more evidences concerning the expansion of rubber plantations lead to the negative influence to local regional hydrology. It is vital to explore the impact of climate change and rubber (Hevea brasiliensis) plantation expansion on reference evapotranspiration (ET0) for the sustainable and efficient use of regional water resources. In this study, the spatiotemporal variation of ET0 as well as its relationship in rubber plantations area in Xishuangbanna from 1970–2017 were analyzed by using trend, correlation and contribution analysis. The results showed that the rubber plantation was 12,768 ha yr–1 from 1990 to 2017 in Xishuangbanna, and nearly 40.8% of new rubber plantations expanded above 900 m in altitude from 2000 to 2017. Sunshine duration and average relative humidity were the key meteorological factors that affect ET0 in Xishuangbanna, with the sensitivity coefficient of 0.51 and 0.35, respectively. The multiyear relative change of ET0 in Xishuangbanna was 9.18%, and the total contribution of major climate factors was 7.87% during 1970 and 2017. The average relative humidity in the plantation area decreases, which directly leads to the increase of ET0. The amount of ET0 change from 2000 to 2017 affected by climate change increased at 3.13 mm/10a, whereas it was 2.17 mm/10a affected by the expansion of rubber plantations by quantitative separation. ET0 was significantly affected by climate change but intensified by the expansion of rubber plantation.

Copyright of Electric Drive is the property of Electric Drive Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The slab model has been used for parameter estimation from the measurement performed by the Pulse Transient Technique. The estimation of thermophysical parameters was done on carbonate rock sample. In addition to basic thermal parameter for example thermal diffusivity, thermal conductivity and specific heat capacity, the slab model takes into account the heat capacity of the heat source, as well as the heat transfer coefficient between the heat source and the sample. The thermophysical parameters were estimated for the case when thermal conductive paste as a heat contact agent was not used for the measurements. The paste contains silicone oil that penetrates into the porous stone material and thus causes irreversible changes of properties during the measurement so we decided not to use it. The experiment was done with dry contacts at the interfaces that causes the disturbances in the measurement that have been introduced and resolved using the slab model. Uncertainty analysis of the estimation of the parameters by the slab model was done for real measurements conducted on the carbonate rock. In this paper we analyzed the quality of the temperature response fit in dependency on the originally free fitted parameters of the heat transfer coefficient and the heat capacity of the heat source that was replaced by constant values in two steps. The heat capacity of the heat source was calculated from the material properties, e.g., the nickel and Kapton. The fit results obtained by the slab model were compared with the data obtained by the ideal and cuboid model. The analysis of the sensitivity coefficients and calculated uncertainties of estimated parameters with the slab model help to improve the accuracy of parameter estimation.

The author of article suggests a method to evaluate the efficiency of using the transport services potential taking into consideration the share of services estimated in gross added value and output present in a region, employment level, investment supply, international competitiveness, the structure of taxes paid, and the shadow rate of business activity. Positive dynamics of the integrated efficiency value in using the transport services potential has been determined in the majority of the Ukrainian regions in the years 2013-2018. A sensitivity coefficient has been estimated for every variable in the integrated efficiency value in using the transport services potential. Substantial sensitivity of the integrated value to changes in the shadow rate level in transportation services is typical for the majority of the Ukrainian regions. On grouping the Ukrainian regions on the basis of sensitivity coefficient of the integrated value to changes in the shadow rate level in transportation services in 2018, the author has identified the regions with high, medium and low sensitivity and described the peculiarities of such groups according to their main features. The main causes of raising the efficiency of using the transport services potential have been determined, namely: unshadowing of enterprises activity; increasing the share of profitable enterprises in the total number of enterprises providing transportation services; increasing the share of the personal income tax in the total of taxes paid by enterprises; employment level. A number of measures have been suggested to raise the efficiency of using the transport services potential, to decrease the amount of “shadow” business, to increase business profitability, and to reduce informal employment.

A method has been developed for quantitative and qualitative assessment of the risk of surface water pollution by nitrogen compounds based on the use of the indicator of the total content of inorganic nitrogen forms in water (Ninorg), that is, ( NH4+ + NO2- + NO3-) This indicator is considered as the sensitivity coefficient kn. The choice of the indicator is dictated by the need to protect waters from pollution caused by nitrogen compounds during their flow from agricultural sources (Directive 91/676 /EU). The experience of developed countries has shown that nitrogen compounds degrade the quality of water and prevent the achievement of a "good ecological state" of water bodies. For territories with developed agriculture, it is important to establish environmental risks of damage depending on the degree of nitrogen pollution. Quantitative assessments of environmental risk are provided on the basis of a probabilistic approach. The risk was calculated as the product of the probability of a hazardous event occurring multiplied by the consequences of this event. The consequences of river pollution with nitrogen compounds were assessed as the ratio of the total concentration of nitrogen compounds (sensitivity index kn) to its threshold value (50 mg/dm³ or 11.3 mgN/dm³). In order to develop a scale for qualitative and quantitative risk assessment, relationships were established between the sensitivity indicators kн and the risk indicators R' for individual rivers, and for the study area as a whole, by means of spatio-temporal generalization. The probabilistic characteristics of possible environmental damage were determined on the basis of the obtained regression equations of the form R'=f(kn) and the statistical law of distribution of the risk value R'. The developed method will make it possible to determine the rank of the risk zone and the probability of getting into it, depending on the given sensitivity indicator kn [ABSTRACT FROM AUTHOR]

The development of the adjoint state method for the system of partial differential equations (PDEs) describing radionuclide transport in heterogeneous discrete fractured porous media in steady‐state regime is presented in this study for both continuous and discrete adjoint approaches. The continuous adjoint approach has its own advantage in the sense that the adjoint system can be derived in terms of PDEs which can be solved analytically for specific performance measures. These PDEs can then be used to obtain a physical interpretation of the adjoint state functions. The discrete adjoint approach permits a simpler mathematical treatment based on the use of the same matrix (or its transpose) of the linear system of the discretized transport equations referring to from hereon as the forward problem. Analytical solutions for both the forward problem and its associated adjoint problem have been derived for radionuclide transport in layered formations including a fracture using an analytical inversion of tridiagonal matrices. A set of 14 formulas of sensitivity coefficients with respect to pertinent system parameters has been derived and presented in integral forms. Analytical results have been compared with numerical results and have shown excellent agreements. The discrete adjoint approach has been coupled with the differential sensitivity analysis method and applied to a real field case involving the performance assessment of a site currently being considered for underground nuclear storage in northern Switzerland, Zürich Nordost. The results show that when a fracture is present in the vicinity of waste repository, the state parameter controlling flow through the fracture, referred to herein as fracture transmissivity, is among the important parameters which should be considered in sensitivity analysis studies. Key Points: A full mathematical/numerical adjoint sensitivity model for steady‐state RN transport in heterogeneous discrete fractured media is presentedAnalytical solutions for concentrations and adjoint states have been derived for the case of layered formations including a fractureThe developed adjoint approach has been coupled with the differential sensitivity analysis method and applied to a real field case [ABSTRACT FROM AUTHOR]