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Copyright of Gazi Journal of Economics & Business is the property of Gazi Journal of Economics & Business 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.)

Due to the advantages of no loss of pressure and wide range, ultrasonic gas meter is becoming a hot research and application at home and abroad. For low power ultrasonic gas meter, a key problem is to improve the precision and stability of the small flow point measurement with the impact of circuit and environment and the influence of turbulence and pulsating flow. In this paper, the ultrasonic propagation time values and their difference values are achieved by using the method of threshold value and the one-half VCC "zero" point detection. The feature point of the arrival time is defined by the threshold value of the echo, which is the zero-crossing point of the next echo period. Propagation time and the differences can be obtained from several feature points that satisfy the threshold of echo. The measurement value at each time is obtained through the average filter process of these difference values. By using the improved Kalman filtering algorithm in flow measurement data processing and adjusting the values of Q and R, the measuring accuracy and stability are improved, respectively, in the small flow point affected by the disturbance and pulsating flow. The latest application circuit introduced by TI company has been used in the ultrasonic gas meter circuit and system design, and the calibration experiment of ultrasonic gas meter has been completed. The experimental results show that the measurement accuracy and repeatability can meet the requirements of the application. [ABSTRACT FROM AUTHOR]

• We propose a method to determine the solar albedo of pavement and embankment slope surfaces. • The solar albedo characteristics of different embankment slopes were evaluated by the proposed method. • A structural solution to improve the thermal stability of permafrost embankment is tentatively proposed. • The applicability of different albedo measurement methods for slopes is analyzed. Roadways built in permafrost regions are more sensitive to the thermal disturbance caused by the natural environment and engineering construction activities. The construction of the embankment changes the albedo characteristics of the natural ground surfaces. Dark asphalt pavement absorbs a huge amount of solar radiation into the permafrost embankment, which leads to the thawing of frozen soil and freezing-thawing diseases of the embankment. Besides, the south-facing slope of the high-fill embankment is exposed to longer and stronger insolation than the north-facing slope annually. It gives rise to the thermal asymmetrical problem and differential settlement across the embankment. To solve above problems and further improve the thermal stability of permafrost embankment, we study the solar albedo characteristics of pavement and embankment slope surfaces in permafrost regions. In this study, an albedo measurement method is proposed for both pavement surface and slope surfaces. The method is validated by in-situ experiments and compared with traditional albedo measurement methods. Meanwhile, we measure the albedo values of the permafrost embankment surfaces along the G109 Highway in high latitude permafrost regions by using the proposed method. The results show that these embankment surfaces absorb a lot of solar radiation for a long time due to the low albedo. Comparing the measured results and remote sensing data, we carry out a comprehensive analysis of the albedo characteristics of permafrost embankment surfaces. Based on these findings, a preliminary solution is put forward to improve the thermal stability of permafrost embankment and decrease embankment diseases. [ABSTRACT FROM AUTHOR]

Summary: The number of large photovoltaic (PV) power plants is increasing around the world. Energy sale usually follows demand contracts with clearly defined obligations, subject to nonsupply penalties. Not supplying the amount of contracted energy is a critical issue to PV plant performance, which can be mitigated with operation and maintenance (O&M) good practices. Furthermore, as the PV plant ages, O&M practices become increasingly important to improve or maintain a good performance. Performance assessment is a complex process that involves several parameters to collect, indicators to measure, and action plans to solve the identified problems. The objective of this study is to identify relevant factors in performance evaluation of O&M practices of medium to large PV plants. Through a systematic literature review and Delphi method with specialists, 33 key performance indicators (KPIs) were determined and classified in operation or maintenance categories, and further in technical or economic subcategories. This paper also organized a set of parameters that PV plant managers should collect to determine the KPIs and evaluate the O&M practices performance. Efficient management of O&M practices results in an indirect increase in generation capacity, as well as ensuring compliance with electricity supply contracts. [ABSTRACT FROM AUTHOR]

China's rental housing market has just started to develop in recent years. It is relatively imperfect and lacks a clear reference for the pricing of rents, which is not fully transparent. A study on the rent formation mechanism of rental housing has policy implications for the construction of a guiding price for the rental housing market and the establishment of a reference basis for the pricing of subsidized housing. Referring to the definition of a benchmark land price, we use data from Beijing to innovatively introduce the concept of benchmark rent. Based on hedonic price theory and the driving factors of benchmark rent, a system of indicators is constructed to explore the mechanism of influencing factors at meso and micro levels on the benchmark rent of market-based rental housing. After LaGrange and robustness tests, it is found that the spatial error model (SEM) is more suitable for benchmark rent determination. We conclude that benchmark rents are affected by spatial relationships caused by spatial heterogeneity and dependency, and that there is significant spatial variation in the factors affecting market-based rental housing benchmark rents. The determination of the benchmark rent can be used as a guiding signal for the market, as a clear signal expectation for the market, government, and tenants. [ABSTRACT FROM AUTHOR]

ABSTRACT The measurement method (MM) and the land-use (LU) are two soil structure-related attributes that are available in infiltration experiments. This study aims to hypothesize that measurement technique and land-use might be good predictors of the performance of infiltration parameter values and models. The Soil Water Infiltration Global (SWIG), which includes about 5000 experiments worldwide and assembled in the Institute of Agrosphere in Jülich, Germany, was used. Except for the known properties such as texture, measurement method, and land-use, changes were observed in organic carbon content, saturated hydraulic conductivity, bulk density, pH, initial water content, and the electrical conductivity of saturated paste. Horton and Mezencev models outperformed from Green and Amp and Two-term Philip models, hence it has been seen that Horton and Mezencev models could be preferred according to the measurement method. To determine the most influential predictors of these two models’ parameters, the machine learning method “regression trees” was applied. In 80 % of cases for both models, the textural class, the MM (40 % of cases), and the LU were found as the most influential predictors. The accuracy of parameter estimates increased when a subset of measurements was used with the same method to estimate infiltration parameters. Textural class, LU, bulk density, and K sat were determined as the most influential predictors for the parameters of the Horton. However, textural class, LU, and organic carbon content became most important in the case of the Mezencev model. Overall, estimates of the infiltration equation parameters can be more accurate if they have been developed for the same MM as in the task at hand. The MM and the LU provide useful surrogate information about the effect of soil structure on infiltration.

[Display omitted] • Quick measurement method of three components was established based on PT-TGA. • The method can be applicated with high heating rates up to 300 °C/min. • The time for three-component content measuring test can be as short as 3 min. • Maximum deviation of relative contents of three components was less than 3.32%. Cellulose, hemicellulose, and lignin are the major components of lignocellulosic biomass, and fast and accurate measurement of the three components' content is beneficial for the efficient application of biomass. However, the current chemical dissolution and titration method was tedious and time-consuming. In this study, a quick determination method of three components in biomass was developed for determining their contents based on a photo-thermal thermo-gravimetric analyzer (PT-TGA). Cellulose was modeled using a single F1 model, while hemicellulose and lignin were fitted with two consecutive processes according to their pyrolysis characteristic with F2 and F1 models. Using the kinetic parameters obtained from the fast pyrolysis of cellulose, hemicellulose and lignin on the PT-TGA, the contents of the three components in biomass samples were calculated by fitting the DTG curves with different peaks. Under the heating rate of 300 °C /min, the relative content deviation of the three components of rice straw was less than 2.00 % with the measurement time within 3 min. Furthermore, coconut shell and pine were used to verify that the maximum difference determined by the kinetic fitting method and the chemical method was only 3.32 %, demonstrating that the method could reliably and rapidly measure the contents of the three components in lignocellulosic biomass. This study provided a fast and effective method for determining the relative content of biomass components. [ABSTRACT FROM AUTHOR]

Among environment contaminants, 210Pb and 210Po have gained significant research attention due to their radioactive toxicity. Moss, with its exceptional adsorption capability for these radionuclides, serves as an indicator for environmental 210Pb and 210Po pollution. The paper reviews a total of 138 articles, summarizing the common methods and analytical results of 210Pb and 210Po research in moss. It elucidates the accumulation characteristics of 210Pb and 210Po in moss, discusses current research challenges, potential solutions, and future prospects in this field. Existing literature indicates limitations in common measurement techniques for 210Pb and 210Po in moss, characterized by high detection limits or lengthy sample processing. The concentration of 210Pb and 210Po within moss display substantial variations across different regions worldwide, ranging from

Two problems associated with distinguishing measurement problem theory from measurement theory are described. The first issue to be addressed is that of harmonizing the definition of the term "measurement" due to a basic terminological confusion between measurements, methods, measurement procedures, and methods for solving measurement problems, including in the International Vocabulary of Metrology, i.e., the problem of distinguishing between measurements and calculations. The second problem arises from the inadequacy of mathematical models representing measurement objects. A solution to these problems is presented in terms of measurement problem theory. [ABSTRACT FROM AUTHOR]

Combining fiber Bragg grating (FBG) sensors and finite element simulation analysis, an online monitoring method for non-invasive distributed flow velocity in pipelines has been proposed. A placement strategy has been proposed for the deployment of these FBG sensors to ensure effective sensing of strain. The cross-sensitivity problem of FBG sensors can be solved by differential FBG measurements. The principle of online monitoring of flow velocity based on the flow velocity function and finite element analysis is described and derived. Finite element analysis results show the $\boldsymbol {\varepsilon }_{1}- \boldsymbol {\varepsilon }_{2}$ at 45° of the elbow of the bend is quadratically proportional to the flow velocity. Meanwhile, the feasibility of the method is verified by experiments. The calibration results show a fitted correlation coefficient R2 = 0.9982 in the velocity range of 4.25-10.62m/s, fitted by least squares to the wavelength data. The repeatability error of the flow measurement of the proposed sensor is no more than 5.06%FS. Compared with the existing literature, the method proposed in this paper has a wider range of flow velocity measurement and applications, especially suitable for applications with strong electromagnetic interference capability and harsher environment, showing great potential for engineering applications, especially in the distributed detection of long-distance pipeline networks. [ABSTRACT FROM AUTHOR]

• A measuring method of single particle emissivity at high temperature is proposed. • The effect of particle diameter on spectral emissivity is investigated. • The expanded uncertainty of the experimental system at 800 °C is 1.380%. It has a very broad prospect to use solid particles as the working medium in the solar collector of concentrated solar power generation system. The emissivity of a particle has an undeniable effect on the efficiency of a solid particle receiver. However, the spectral emissivity of a single particle at high temperature is rarely reported. In this work, an experimental method for measuring the spectral emissivity of a single particle at high temperature is established. This method is based on a self-designed heater, Fourier transform infrared spectrometer (FTIR) and a blackbody furnace. It can measure the spectral emissivity of a single particle at high-temperature of 500-900°C, and the test wavelength range is 2.5–25 μm. By measuring the spectral emissivity of 3–5 mm diameter particles, the influence of particle size on the emissivity was obtained. The expanded uncertainty of spectral emissivity of 3 mm SiC particles at 800°C is 1.380%. [ABSTRACT FROM AUTHOR]

Issues associated with improving the maneuverability and operating speed of a mechatronic profiler, as well as extending the profile measurement range for various surfaces, are considered. In order to solve these problems, a method was proposed for measuring a surface profile along a given trajectory using a mechatronic profiler that provides parallel control of sensor drives. A system for controlling a mechatronic profiler characterized by distributed control of drives is described, effectively implementing the programmed movements of the profiler's laser sensor. The described control system improves the accuracy, sensitivity, speed, and reliability of the mechatronic profiler during operation, as well as reducing measurement and calibration time while significantly increasing the accuracy of measurement results. In addition, a developed information and measurement system of the mechatronic profiler is presented, along with a specification of software for controlling the electric drives of a mechatronic profiler. The following metrological characteristics of the mechatronic profiler were established and confirmed during verification: range of measuring the sensor-to-surface distance – 100–500 mm; maximum permissible absolute measurement error – ±0.05% of the range; circumferential measurement range – 0–360°; maximum permissible error of the rotary encoder ±30″. The results of surface profile measurements performed in polar coordinates for a corrugated sheet having a downward deflection amounting to 13.8 ± 0.05 mm in the cross-section are presented in graphic form. The study results can be used in various economic sectors: mechanical engineering, agriculture, construction, etc. [ABSTRACT FROM AUTHOR]

The measurement of magnetostriction characteristics of grain-oriented electrical steel strip under an external compressive stress has always been a main focus in the process of magnetostriction measurement. There are difficulties in the measurement of magnetostriction, especially under compressive stress, mainly because the thickness of test specimen is small, and the test specimen is very easy to deform under the compressive stress. A weight should be placed on the test specimen to prevent a deformation of the test specimen when the measurement of magnetostriction characteristics under an externally compressive stress according to the IEC/TR 62581:2010. But how much weight and how to place aren't concerned in IEC standard. In this paper, different weights were placed on the grain-oriented electrical steel test specimen under external compressive stress and zero stress. Through analyzed the measured magnetostriction data under different weights to determine the optimal measurement method of grain-oriented electrical steel strip under compressive stress and zero stress. The purpose of this paper is to find the most accurate and high reproducibility measurement method of magnetostriction, which can truly reflect the magnetostriction performance of grain-oriented electrical steel. [ABSTRACT FROM AUTHOR]

Grounding electrode is an indispensable part in HVDC transmission projects. During its design and safety evaluation, step voltage is a crucial aspect. By reviewing and sorting out the present standards involving step voltage measurement and its safety limit, this paper illustrates the contradiction between the measurement methods and the safety evaluation criteria. Reasons for the contradiction are explained by analyzing the principal of step voltage measurement and safety evaluation. The Open-circuit step voltage measurement method and the measurement method with a human body equivalent resistance paralleled are compared to find out their advantages and disadvantages. Suitable circumstances and corresponding safety criteria of these two methods are put forward. Method proposed in this paper can be applied to step voltage measurement and safety evaluation of HVDC grounding electrode, providing reference when revising the related standards. [ABSTRACT FROM AUTHOR]

The decreasing size of minerals that need to be separated with flotation technique has posed a rigorous challenge to conventional flotation techniques. It's urgent for the researchers working in the field of minerals processing to develop a kind of new, efficient but economic flotation technique. In the past dozens of years, a mass of reports regarding the application of bulk nanobubbles in flotation has been emerging and the positive effect of bulk nanobubbles has been widely verified by the flotation performance of various minerals. The rapid and brilliant progresses made in this field and the huge potential of application in minerals processing motivated the present work. In this work, we reviewed various techniques to produce bulk nanobubbles and the widely used measurement techniques for bulk nanobubbles and analyzed the disadvantages of them. These measurement techniques fail to identify the real identification of nanoentities, which have resulted in debates about the real identification of the observed nanoentities. Then, we reviewed the methods as in detail as possible that were proposed by many researchers to identify the identification of nanoentities, which should help close the relevant debate. Next, considering it that flotation is usually performed in such a liquid environment with complex physical and chemical properties (pH, salt, surfactant, ultrasonication et al.), we reviewed the responses of bulk nanobubbles to external stimuli including the factors described above. Only the bulk nanobubbles keep stable all the time during a flotation process does it make sense to employ bulk nanobubbles for flotation. In the last section, we reviewed the underlying mechanism of how the flotation performance was improved in the presence of bulk nanobubbles. The aim of this review is to provide researchers who are working in the area of mineral processing with rough information about nanobubbles from the field of interface physics and shed some light on developing new techniques for fine particle separation. [Display omitted] [ABSTRACT FROM AUTHOR]

Summary: Temperature is a key control over biological activities from the cellular to the ecosystem scales. However, direct, high‐precision measurements of surface temperature of small objects, such as leaves, under field conditions with large variations in ambient conditions remain rare. Contact methods, such as thermocouples, are prone to large errors. The use of noncontact remote‐sensing methods, such as thermal infrared measurements, provides an ideal solution, but their accuracy has been low (c. 2°C) owing to the necessity for corrections for material emissivity and fluctuations in background radiation Lbg.A novel 'dual‐reference' method was developed to increase the accuracy of infrared needle‐leaf surface temperature measurements in the field. It accounts for variations in Lbg and corrects for the systematic camera offset using two reference plates.We accurately captured surface temperature and leaf‐to‐air temperature differences of needle‐leaves in a forest ecosystem with large diurnal and seasonal temperature fluctuations with an uncertainty of ± 0.23°C and ± 0.28°C, respectively.Routine high‐precision leaf temperature measurements even under harsh field conditions, such as demonstrated here, opens the way for investigating a wide range of leaf‐scale processes and their dynamics. [ABSTRACT FROM AUTHOR]

This article discusses the issues of acceptance by consumers of various combinations of signals from global navigation satellite systems and control of the parameters of each of the separate signals. Existing methods for controlling the partial characteristics of signals are based on correlation processing, which results in the loss of measurement information and signal averaging. To eliminate these disadvantages, a method for measuring the partial power of navigation signals with frequency and code division was developed. The initial data for the method include the results of measurements of the spectral power density of the sum of signals, as well as information on the shape of the partial spectral power densities. A mathematical model of the sum of signals with overlapping spectra was analyzed. The signal powers correlated to weighting factors at partial spectral power densities. A system of equations for weight coefficients was compiled and solved by Tikhonov's method. The metrological characteristics of the method were practically investigated. The results of this study can be used to solve problems of monitoring the technical condition of navigation spacecraft. [ABSTRACT FROM AUTHOR]

The article focuses on the determination of the acoustic properties (sound transmission loss, sound absorption and transmission coefficient under acoustic plane wave excitation) of membrane-type of specimens by means of a combination of incident plane wave sound pressure and membrane surface displacement information, measuring the sound pressure with a microphone and the membrane displacement by means of a laser Doppler vibrometer. An overview of known measurement methods and the theoretical background of the proposed so-called mobility-based method (MM) is presented. The proposed method was compared with the conventional methods for sound transmission loss and absorption measurement in the impedance tube, both numerically and experimentally. Finite element model (FEM) simulation results of two single layer membrane samples of different shape configurations were compared, amongst which six different variations of the backing wall termination. Four different approaches to determine the sound transmission loss and two methods to determine sound absorption properties of the membranes were compared. Subsequently, the proposed method was tested in a laboratory environment. The proposed MM method can be possibly used to measure the vibro-acoustic properties of building parts in situ. [ABSTRACT FROM AUTHOR]

A method for measuring the diffuse field sound absorption coefficient of a material using sound field synthesis is proposed. A planar loudspeaker array is first used to generate acoustic plane waves with variable incidence angle on the surface of a material under test. Using a two-microphone probe positioned closely to the sample’s surface, the angle-dependent sound absorption coefficients are then estimated. Finally, the diffuse field absorption coefficient is computed following Paris formula. Numerical simulations are used to evaluate the respective effects of the maximum incidence angle value and the number of individual incidence angles that are required for a robust calculation of the diffuse sound field absorption. Measurements are conducted on three different materials and compared with either simulation results obtained using the Johnson-Champoux-Allard theory, or with measurement results obtained using the standard reverberation chamber method. For all considered materials and over a wide frequency range, the proposed method leads to results that are in better agreement with theoretical predictions than those obtained using standardized methods.

This article provides an overview of the development history and advantages and disadvantages of measurement methods for soft tissue properties of the plantar foot. The measurement of soft tissue properties is essential for understanding the biomechanical characteristics and function of the foot, as well as for designing and evaluating orthotic devices and footwear. Various methods have been developed to measure the properties of plantar soft tissues, including ultrasound imaging, indentation testing, magnetic resonance elastography, and shear wave elastography. Each method has its own strengths and limitations, and choosing the most appropriate method depends on the specific research or clinical objectives. This review aims to assist researchers and clinicians in selecting the most suitable measurement method for their specific needs., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Yang, Peng, Liu, Liu and Lu.)

This research introduces a systematic framework for calculating sample size in studies focusing on enteric methane (CH 4 , g/kg of DMI) yield reduction in dairy cows. Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a comprehensive search across the Web of Science, Scopus, and PubMed Central databases for studies published from 2012 to 2023. The inclusion criteria were: studies reporting CH 4 yield and its variability in dairy cows, employing specific experimental designs (Latin Square Design (LSD), Crossover Design, Randomized Complete Block Design (RCBD), and Repeated Measures Design) and measurement methods (Open-circuit respirometry chambers (RC), the GreenFeed system, and the sulfur hexafluoride tracer technique), conducted in Canada, the United States and Europe. A total of 150 studies, which included 177 reports, met our criteria and were included in the database. Our methodology for using the database for sample size calculations began by defining 6 CH 4 yield reduction levels (5, 10, 15, 20, 30, and 50%). Utilizing an adjusted Cohen's f formula and a power analysis we calculated the sample sizes required for these reductions in balanced LSD and RCBD reports from studies involving 3 or 4 treatments. The results indicate that within-subject studies (i.e., LSD) require smaller sample sizes to detect CH 4 yield reductions compared with between-subject studies (i.e., RCBD). Although experiments using RC typically require fewer individuals due to their higher accuracy, our results demonstrate that this expected advantage is not evident in reports from RCBD studies with 4 treatments. A key innovation of this research is the development of a web-based tool that simplifies the process of sample size calculation (samplesizecalculator.ucdavis.edu). Developed using Python, this tool leverages the extensive database to provide tailored sample size recommendations for specific experimental scenarios. It ensures that experiments are adequately powered to detect meaningful differences in CH 4 emissions, thereby contributing to the scientific rigor of studies in this critical area of environmental and agricultural research. With its user-friendly interface and robust backend calculations, this tool represents a significant advancement in the methodology for planning and executing CH 4 emission studies in dairy cows, aligning with global efforts toward sustainable agricultural practices and environmental conservation., (The Authors. Published by Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).)

This paper proposes an optical amplification method of measuring the minute displacement of a laser beam. The relationship between the displacement of the incident laser beam and the reflective beam is calculated by geometric optical analysis. The equation of displacement is derived to calculate its magnification. We demonstrate that by employing the reflection characteristics of a cylindrical mirror, the minute-displacement of a laser beam can be enlarged to the millimetre level. Experimental results confirm that the magnification can be hundreds of times. Such an enlarged displacement measuring system of laser beam could be suitable for the study of Goos–Hänchen shift. [ABSTRACT FROM AUTHOR]

The surface residual stress significantly influences the performance of gears. The residual stresses of different grinding positions on the gear surface are different. Focusing on the gear profile grinding process, the residual stress distribution of gear tooth flank is investigated. To measure the residual stress of gear tooth accurately, a specific measurement method, including adjustment angle calculation model and alignment fixture, is carried out. The measured results with the proposed method are much better, and differences of residual stresses among measured positions are discussed. Then, considering the variation of chip geometry, a gear grinding model is proposed to analyze the residual stress distribution of gear tooth flank. The changing trend of the section area of the cutting chip calculated by the proposed grinding model matches the changing trend of measured results of the residual stress distribution. Finally, experiments are conducted, and the grinding model is verified from the perspective of cutting parameters. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology 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.)

Rapid urban expansion and climate change have prompted further investigations into urban thermal climates and the development of local climate zone (LCZ) classification systems. LCZs, proposed 10 years ago, comprise a new and systematic classification of field sites for heat island studies to provide a reference for future LCZ research, so that scholars can understand what research has been done and identify future research trends. We analyzed LCZ studies in a database from 2012 to the present, and identified recurring themes using VOSviewer software, including LCZ mapping, measurement methods, thermal environments, and outdoor thermal comfort, among others. A systematic evaluation was performed using bibliometric analysis in the PRISMA framework—190 relevant studies were selected for subsequent analysis. Descriptive analysis showed that LCZ research has received increasing attention, particularly in China, where more than 60% of the LCZ studies were conducted. The results showed that the maximum number of articles on all themes was 57 articles on LCZ mapping, followed by studies of the thermal environment (UHI/SLT). It is hoped that this article will provide scholars in this area with an understanding of the research that has been conducted and the methods used, and provide insight into future research directions.

A testing apparatus, namely, touch sensation tester for fabrics (TST-F), was introduced to evaluate the touch properties of fabrics. This novel apparatus enables a simultaneous measurement of different mechanical properties of the sample with a combination of temporal and spatial resolution, enhancing the measuring accuracy and reliability of the time-dependent physical behavior of textile materials. The prototype of the TST-F and details of the measurement principle were exhibited, and nine indices relating to fabric’s deformation performance during wearing were extracted from measured force–displacement curve to characterize the mechanical properties relating to fabric’s touch sensory attributes. Stepwise regression was used to develop a series of prediction models for assessing human sensations toward bending stiffness, compression softness, and stretching tightness of fabrics by linking the measured indices to subjective assessments. Moreover, the prediction models were validated using a set of independent fabric samples. Results show that prediction values have good agreements with subjective grades as indicated by the coefficients of determination R2 higher than 0.887 and reasonably low mean square errors (MSEs). Also, the repeatability of the measured curves was confirmed by statistical analysis. Therefore, the TST-F provides an alternative to evaluate the touch properties of fabrics objectively. [ABSTRACT FROM AUTHOR]

Radon natural is the main cause of lung cancer in non-smokers. Therefore, the study of the behavior of radon and its descendants in indoor air is of the highest importance, in order to limit the risk of radiation dose due to inhalation of radon by members of the public. This article focuses to study the effects of meteorological parameters on the concentration and distribution of radon in a traditional hammam by both numerical simulations and experiments. The results of the numerical simulations are qualitative and show that the concentration and distribution of radon decrease when the ventilation rate increase, as well as, when the temperature increases, however, it increases with the increase in relative humidity. The results obtained by the numerical simulations were in agreement with those obtained experimentally with a maximum deviation of 7%. Numerical simulations allow a better estimate of the distribution of radon in indoor air. [ABSTRACT FROM AUTHOR]

In the ecosystem public opinion communication network composed of individual nodes and their propagation paths, each network node is not equally important in the process of ecological public opinion dissemination. It is of great significance for the control and management of ecological public opinion communication network to study and analyze the key network nodes and their mutual ecological public opinion communication relations in the ecological public opinion communication network. Based on the investigation of the complex network environment theory, this paper constructs the ecological public opinion communication network map. This paper measures the nodes of ecological public opinion communication network from the aspects of degree centrality, betweenness centrality, kernel centrality, eccentricity centrality, compactness centrality and eigenvector centrality. Finally, a simplified diagram of part of the structure of the ecological public opinion communication network is analyzed. The verification results show that different measurement methods and indicators can better measure and identify the key nodes in the ecological public opinion communication network from different angles. The results provide a reference for researchers and managers to analyze the ecological public opinion communication network and identify key nodes from the local and overall perspectives. [ABSTRACT FROM AUTHOR]

[Display omitted] • A G s measurement method based on the flow-around principle was proposed. • The mathematical model of the signal transformation process was established. • The measurement uncertainty of the device was evaluated less than 2.0 %. • The measurement device was semi-quantitatively verified by the industrial test. The solid circulation rate (G s) is a key parameter for the design and operation of a circulating fluidized bed (CFB) industrial equipment, while the detection and measurement of the G s value in an actual industrial CFB equipment remains difficult. To fill this gap, a method for the G s measurement based on the flow-around principle was proposed in this study. The mathematical model for the signal transformation was established along the path "detected strain value – impact force – particle velocity – G s value", and the corresponding measurement device was also developed. The performance of the G s measurement device was quantitatively validated in cold-state experiments and semi-quantitatively verified in an industrial trial in a CFB boiler. The results of a theoretical analysis indicate that the detected strain linearly increased with the impact force received by the intrusive spherical obstacle, and the slope coefficient was determined as per the experiment. The correlation of the impact force to the particle flow velocity was proposed and fitted using the experimental data. The computational particle fluid dynamics method was applied to simulate the particle flow field in the standpipe of the CFB boiler to determine the installation location of the G s measurement device. The lab-scale cold-state experiments showed that the relative standard uncertainty of the G s measurement using the device built in the present study was less than 2.0 %. This device was then applied in an industrial trial in a 116 MW th CFB boiler and the results proved the feasibility and applicability of the proposed G s measurement method. [ABSTRACT FROM AUTHOR]

Quality evaluation is very important for haptic rendering. In this paper, an objective evaluation method for a haptic rendering system based on haptic perception features is proposed. In the method, the haptic rendering process is compared to the real world perception process in a simple standardized procedure based on feature extraction and data analysis. A complete evaluation process for a simple haptic rendering task of pressing a virtual spring is presented as an example to explain the method in detail. Compared with the traditional objective method based on error statistics, the method is more concerned about the consistency of human subjective feelings rather than physical parameters, which makes the evaluation process more consistent with the haptic perception mechanism. The results of comparative analysis show that the method presented in this paper is simple, gives reliable results reflecting the consistency with subjective feeling and has a better discrimination ability for different kinds of devices and algorithms compared with the traditional evaluation methods.

China’s rental housing market has just started to develop in recent years. It is relatively imperfect and lacks a clear reference for the pricing of rents, which is not fully transparent. A study on the rent formation mechanism of rental housing has policy implications for the construction of a guiding price for the rental housing market and the establishment of a reference basis for the pricing of subsidized housing. Referring to the definition of a benchmark land price, we use data from Beijing to innovatively introduce the concept of benchmark rent. Based on hedonic price theory and the driving factors of benchmark rent, a system of indicators is constructed to explore the mechanism of influencing factors at meso and micro levels on the benchmark rent of market-based rental housing. After LaGrange and robustness tests, it is found that the spatial error model (SEM) is more suitable for benchmark rent determination. We conclude that benchmark rents are affected by spatial relationships caused by spatial heterogeneity and dependency, and that there is significant spatial variation in the factors affecting market-based rental housing benchmark rents. The determination of the benchmark rent can be used as a guiding signal for the market, as a clear signal expectation for the market, government, and tenants.

The ice concentration and velocity are two key parameters for the Yellow River ice protection, which can be extracted by image recognition method. The videos were field acquired by the remote video monitoring system of the Yellow River ice protection. The measurement of ice concentration had two steps. Firstly, the video was converted to single frame images. Then the single frame images were binarized. The ice regions were recognized by image segmentation and the ice concentration could be counted easily. For the measurement of ice velocity, the video image sequence was obtained by the camera equipment. Then the positions of each image’s feature points were marked by the dense optical flow method and the feature points were tracked to obtain the moving distance. Finally, the ice velocity was calculated according to the interval time. [ABSTRACT FROM AUTHOR]

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In a comparison of two measurement methods using nonparametric criteria, we established that the measurement results for some exterior features obtained through one method were significantly different from the results obtained using another measurement method. Measurement using Altami Studio 3.4.0® (OOO“Altami”, Saint Petersburg, Russia) allows results to be generated with less trait variability between repeated measurements by one operator, as well as between operators, compared to MBS-9 (LOMO, St. Petersburg, Russia). With the help of an analysis of variance, we established that two factors influence the measurement results: the measurement method and the operator performing the measurement, as well as the interaction of these two factors. Repeated measurements using the software will allow operators to be identified who are prone to less variability of results, as well as control the accuracy of measurements.

Featured Application: This study aims to measure and improve the effectiveness of the multiproduct production system in the manufacturing enterprises precisely. The multiproduct production system has been applied extensively in factories worldwide due to the diverse consumption habits of consumers. However, current Overall Equipment Effectiveness (OEE) measurement methods are not suitable for it properly. With the prevailing of multiproduct production system, it is essential to measure the effectiveness accurately in this kind of production system. In order to fill this gap, based on analyzing former OEE models, we propose the multiproduct production system effectiveness (MPSE), including the calculating steps and application framework, in this paper using the heuristic method. This MPSE is verified by a case study. The principal results show that the proposed MPSE can significantly enhance overall production effectiveness and improve the measurement of indicators in the multiproduct production system, which enriches the theory of OEE at the theoretical level and proposes a novel way to measure and improve the effectiveness of the multiproduct production system effectively at the practical level. [ABSTRACT FROM AUTHOR]

• A measurement method for determining the k · A value of household refrigerating appliances is presented. • A latent heat sink is a suitable alternative to the reverse heat leak method. • Air flow and storage temperatures in the refrigerator compartment are comparable to the real operating conditions. • Temperature gradients between the storage room and the ambient of the refrigerating appliances are more realistic. • An age-related increase of the k · A value of between 3.6% and 11.5% was found over a period of 14 months. The increase of the thermal conductivity of PUR foam in the insulation of the cabinet is an important cause for aging processes of household refrigerating appliances. To determine the influence of the PUR foam aging on energy consumption, the development of a new measurement method is necessary because current methods influence the aging behavior of household refrigerators and are therefore not applicable in general. Based on a latent heat sink, constructed as an ice water bucket, a new measurement method is developed to determine the k · A value over time. With this method, the k · A value of four household refrigerating appliances was determined over an interval of 14 months. The k · A value increased between 3.6% and 11.5% during this period. [ABSTRACT FROM AUTHOR]

Due to the effects of discontinuous deformation in fractured rock masses and complex shearing between the rock bolt and the grout, the strain of rock bolt in fractured zone can hardly be measured accurately. A fully-grouted rock bolt was prepared by using 3D printing, and strain gauges were installed inside and outside the bolt respectively. The evolution law of tensile strain in the fully-grouted rock bolt during the fracture propagation process was obtained by uniaxial compression test. It was found that the outer strain gauges were greatly affected by the shear deformation of the grout, and the measurement results are easy to be distorted when the plastic deformation capacity of the grout is high. However, the internal strain gauges could accurately obtain the complete strain of bolt. Finally, the failure process of rock bolt in fractured zone was numerically simulated by FLAC software, the influence of strain gauge location on the measurement results was verified, which further proved the reliability of measurement by strain gauges inside the rock bolt. [ABSTRACT FROM AUTHOR]

In order to solve the problem that it is tedious and time-consuming by using GB / T 29256.5--2012 to test yarn linear density, the number of test yarn stretch length of each sample in the standard method was reduced from 10 to 5, and the average value was used to calculate the yarn linear density. According to the JJF 1059.1--2012, the uncertainty of the results was evaluated by testing the samples with different linear density and blending ratio to confirm whether they met the needs of the intended use or application field. The results show that the relative expanded uncertainty of the test results of all samples are between 0.42% and 2.49%, which meets the requirements of the existing standards; the linear density deviation of the first-class yarn is not less than ± 2.5%.The improved method can be used as a testing method for yarn linear density of woven fabric, which improves the detection efficiency and provides a reliable basis for revising the method standard. [ABSTRACT FROM AUTHOR]

Fluorescence Assay by Gas Expansion (FAGE) has been used to detect ambient levels of OH and HO2 radicals at the Cape Verde Atmospheric Observatory, located in the tropical Atlantic marine boundary layer, during May and June 2007. Midday radical concentrations were high, with maximum concentrations of 9 ×106 molecule cm−3 and 6×108 molecule cm−3 observed for OH and HO2, respectively. A box model incorporating the detailed Master Chemical Mechanism, extended to include halogen chemistry, heterogeneous loss processes and constrained by all available measurements including halogen and nitrogen oxides, has been used to assess the chemical and physical parameters controlling the radical chemistry. The model was able to reproduce the daytime radical concentrations to within the 1 σ measurement uncertainty of 20% during the latter half of the measurement period but significantly under-predicted [HO2] by 39% during the first half of the project. Sensitivity analyses demonstrate that elevated [HCHO] (~2 ppbv) on specific days during the early part of the project, which were much greater than the mean [HCHO] (328 pptv) used to constrain the model, could account for a large portion of the discrepancy between modelled and measured [HO2] at this time. IO and BrO, although present only at a few pptv, constituted ~19% of the instantaneous sinks for HO2, whilst aerosol uptake and surface deposition to the ocean accounted for a further 23% of the HO2 loss at noon. Photolysis of HOI and HOBr accounted for ~13% of the instantaneous OH formation. Taking into account that halogen oxides increase the oxidation of NOx (NO → NO2), and in turn reduce the rate of formation of OH from the reaction of HO2 with NO, OH concentrations were estimated to be 9% higher overall due to the presence of halogens. The increase in modelled OH from halogen chemistry gives an estimated 9% shorter lifetime for methane in this region, and the inclusion of halogen chemistry is necessary to model the observed daily cycle of O3 destruction that is observed at the surface. Due to surface losses, we hypothesise that HO2 concentrations increase with height and therefore contribute a larger fraction of the O3 destruction than at the surface.

The article focuses on the determination of the acoustic properties (sound transmission loss, sound absorption and transmission coefficient under acoustic plane wave excitation) of membrane-type of specimens by means of a combination of incident plane wave sound pressure and membrane surface displacement information, measuring the sound pressure with a microphone and the membrane displacement by means of a laser Doppler vibrometer. An overview of known measurement methods and the theoretical background of the proposed so-called mobility-based method (MM) is presented. The proposed method was compared with the conventional methods for sound transmission loss and absorption measurement in the impedance tube, both numerically and experimentally. Finite element model (FEM) simulation results of two single layer membrane samples of different shape configurations were compared, amongst which six different variations of the backing wall termination. Four different approaches to determine the sound transmission loss and two methods to determine sound absorption properties of the membranes were compared. Subsequently, the proposed method was tested in a laboratory environment. The proposed MM method can be possibly used to measure the vibro-acoustic properties of building parts in situ.

This study investigates a measurement method of thermal diffusivity for samples with arbitrary geometries and unknown material properties. The aim is to curve fit the thermal diffusivity with the use of a numerical simulation and transient temperature measurement inside the object of interest. This approach is designed to assess bulk material properties of an object that has a composite material structure such as underground soil. The method creates the boundary conditions necessary to apply analytical theory found in the literature. It was found that measurements best correlated with theory and simulation at positions between the center and surface of an object.

In Japan, where a safe and secure society has been established, stab proof clothing that are suitable for police and security officers supporting are required. So far, most of the stab-proof clothing is made of the metal plate or thick multi-layered fabric with high-strength fibers. It is commonly used as a stab-proof vest because it cannot cope with the large deformations, which caused by the joints such as arms or neck. This research aims to develop high flexible stab-proof clothing that can be applied in large-deformation part such as joints with high stab-proof performance. We developed a testing device that can measure bending characteristics under the same conditions as when the stab proof clothing is actually worn on the human body. The usefulness of the evaluation method was confirmed. And the factors that affect the bendability of the elbow joint were also be studied. The mechanical properties of the material and the gap between the arm and the cylindrical structure are greatly affected, and the effect of each bending angle on the bending moment is different. We considered the deformation of the material when it bending and then proposed a new stab-resistant material structure and trial production. The cylindrical bending test shows that the flexibility of the new structure is greatly improved. [ABSTRACT FROM AUTHOR]

This study presents a measurement method for a bike frame to solve a problem that usually relies on the digimatic callipers or mechanical molds handled by a human, therefore avoiding a long time process and measurement errors. In such a mechanism, the measured data is based on the handwritten record, and thus a difficulty may occur in further data analysis using the computer. For this reason, this study aims to develop a mathematical model of three‐dimensional geometry especially applied for robotic arm‐based bike frame measurement. The proposed mathematical geometric model effectively integrates the sphere formula with the inner product of normal vector to find four parameters in the sphere formula using only three measured points. Accordingly, the centre coordinate of the check point and its diameter can be calculated accurately and simply. The practical model performance also prooves that all crucial quality checking items such as centre plane offset, inside diameter, axis point and parallelism in different rotating shafts of bike frame can be achieved in term of rapid, robustness and precision. Moreover, the measurement accuracy in the estimated standard deviation and measurement uncertainty using two different bike frames is presented to verify the effectiveness of the proposed model. [ABSTRACT FROM AUTHOR]

Aiming at the inability of low precision ordinary turntable to effectively measure the resolution of the high-precision fiber-optic gyroscope (FOG), this paper proposes a method for a high-precision FOG resolution test based on a low-performance turntable with the earth’s angular velocity as the input value. Taking a two-axis turntable with 1 arc-minute angular precision as an example, the Two-Degrees-Of-Freedom (2-DOF) theoretical angle range is obtained, through stationary gyro biaxial angular position error incremental output analysis. The method can be used for high-precision FOG including, 0.001 deg/h, 0.0001 deg/h, 0.00001 deg/h (three typical accuracies) resolution measurements. The detailed test steps are presented. Simulation results show that traditional test methods fail under the same working conditions, while the proposed method can effectively measure the high-resolution gyro resolution effective coverage within the theoretical angle range of the corresponding two-axis turntable. Experimental results demonstrate that the two-axis turntable based on with 1 arc-minute angular precision can effectively perform a high-precision FOG resolution of 0.005 deg/h. [ABSTRACT FROM AUTHOR]