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2021 ◽  
Vol 13 (24) ◽  
pp. 14051
Author(s):  
Tongdan Gong ◽  
Wenjie Zhang ◽  
Jinhan Liang ◽  
Changqing Lin ◽  
Kai Mao

Controlling the scale of civil buildings is of great significance for energy saving and emission reduction in the construction field. This paper analyzes and extracts the key index parameters for the calculation of various civil building areas, establishes a detailed calculation model of the total civil building area, and constructs three different scenarios to predict various civil building areas in China from 2020 to 2060. Under the three scenarios, the total amount of civil buildings in China will reach a peak of 93.5, 84.6, and 76.3 billion m2 in 2040, 2035, and 2035, respectively. Under the constraints of energy consumption and carbon emission, this paper suggests that civil buildings develop according to the medium control scenario. In 2035, the urban per capita residential area will reach a peak of 42 m2, the urban residential area will reach 43 billion m2, the rural per capita residential area will reach the peak of 55 m2, the rural residential area will reach 20.6 billion m2, and the public building area will reach 21 billion m2. By 2060, the total area of civil buildings will drop to 76.5 billion m2, including 37.1 billion m2 of urban residential buildings, 18.5 billion m2 of rural residential buildings, and 20.9 billion m2 of public buildings.


Sensors ◽  
2021 ◽  
Vol 21 (22) ◽  
pp. 7520
Author(s):  
Jinbao Feng ◽  
Jinhui Wu ◽  
Yu Si ◽  
Yubin Gao ◽  
Ji Liu ◽  
...  

To study the law that governs the complex movements of the mechanism in the process of automatic weapon operation, the velocity tracking test technology of photon Doppler velocimetry is introduced to accurately measure velocity, displacement and acceleration, on the condition that there are long displacement and rapid velocity change. In the traditional way, out of interference signal time-frequency (TF) transformation draws TF distribution, and then by modulus maxima frequency extraction, comes to the law of velocity change. Due to the influence resulting from the change of fundamental signal as well as that of light intensity signal in the test, based on the TF distribution obtained by TF transformation, the traditional modulus maxima frequency extraction can extract frequency signals, but they show abnormal sudden changes at some moments, making the velocity discontinuous, unsmooth and unreal, which brings obvious errors to the subsequent calculation of acceleration and accurate displacement. Addressing the above-mentioned problems, this paper proposes a ridge extracting correction algorithm based on modulus maxima frequency extraction; this method, based on a large number of experiments where rodless cylinders are used to simulate the motion of a gun automatic mechanism, conducts a detailed calculation and analysis of the experimental results. A comparison of the two algorithms’ processing results, in terms of the speed, displacement and acceleration, suggests that the ridge extracting correction algorithm successfully corrects the frequency selection error, which draws a more continuous and, therefore, effective curve of the velocity change, and by so doing, the error of the displacement test (within 1.36 m displacement) is reduced from more than 3.6% to less than 0.58%, and the uncertainty dropped 97.07%. All these show that the accurate measurement of velocity, displacement and acceleration, with sudden and rapid velocity changes considered, is realized successfully.


2021 ◽  
Vol 2042 (1) ◽  
pp. 012175
Author(s):  
Endrit Hoxha ◽  
Rolf André Bohne ◽  
Alexander Passer

Abstract In order to reach the COP21 objectives, solutions with low carbon contents must be used in road projects. However, the identification of the best materials to be implemented in the wearing course of roads is a daily problem faced by stakeholders. To overcome this knowledge gap, the present study demonstrates the environmental impacts of 120 mixtures calculated with simplified and detailed hypotheses and input data. Even though the variability of inputs significantly influences the impacts of the mixtures and do not allow for the identification of the best solutions, on average, warm mix asphalt presented lower impacts than hot mix asphalt or concrete.


Energies ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6673
Author(s):  
Karina Shamilyevna Nurgalieva ◽  
Liliya Albertovna Saychenko ◽  
Masoud Riazi

A number of difficulties may be encountered in the final stages of oil field exploitation, including the formation of asphalt–resin–paraffin deposits (ARPDs). It is expedient to use complex technologies to remove the already formed deposits and prevent the formation of ARPDs. This paper focuses on the complex technology of oil field exploitation. This technology combines both the removal of organic deposits and the prevention of the formation of these deposits in the well bottomhole formation zone (BHFZ) system. The calculations for determining the process parameters of selling the ARPD inhibitor solution into the BHFZ are presented in this article. This complex technology includes the process of ARPD removal by flushing the well and the subsequent injection of the developed ARPD solvent into the BHFZ. In addition, the technology is complemented by a method of preventing the formation of these deposits. This method consists of squeezing the ARPD inhibitor and then pumping it by the selling fluid from five to ten times of the volume. This article contains a detailed calculation of the methodology and provides the diagrams for the solvent and inhibitor injection.


2021 ◽  
pp. 146808742110479
Author(s):  
Alexander D Gelner ◽  
Harald A Beck ◽  
Christian Pastoetter ◽  
Martin Härtl ◽  
Georg Wachtmeister

Polyoxymethylene dimethyl ethers (OME) are promising candidates as substitutes for fossil diesel fuel. A regenerative electricity-based production, using captured airborne carbon dioxide (CO2) and hydrogen (H2) from water electrolysis as reactants, provides a valuable contribution to the energy transition in mobile applications. Besides the possibility of carbon-neutral production, OME offer the advantage of a sootless combustion, which resolves the trade-off between soot and nitrogen oxides (NOx) emissions, and supports the efforts of air pollution control. While the emission behaviour of OME-powered diesel engines in raw exhaust has been studied extensively, interactions between this exhaust and components of the after-treatment system are mainly unknown. This study contains investigations conducted using a urea dosing variation (alpha titration) on a heavy-duty engine in combination with a system for selective catalytic reduction (SCR). These investigations showed a lower NOx reduction efficiency in OME operation in partial load operation compared with the one in fossil diesel operation. This can be attributed, among other reasons, to lower exhaust temperatures in OME operation. However, the high tolerance of OME to exhaust gas recirculation (EGR) compensates for this disadvantage because of the reduction of the raw NOx emission level. The difference in SCR efficiency disappeared at a high load operation point. Additionally, the alpha titration revealed, that urea dosing decreases formaldehyde emission in the SCR system. A pre-conditioned WHSC and WHTC cycle demonstrated the potential of an OME engine with after-treatment in the form of a twin-dosing SCR system for ultra-low emissions. For the specific evaluation of the emissions during these test cycles, this study contains the detailed calculation of the required factors – so-called ‘ u-values’– for OME exhaust according to the technical standard UN/ECE R49.


2021 ◽  
Vol 11 (19) ◽  
pp. 8816
Author(s):  
Lianmeng Chen ◽  
Yihong Zeng ◽  
Weifeng Gao ◽  
Yijie Liu ◽  
Yiyi Zhou

As the current literature lacks effective nonlinear robustness evaluation method and optimal design theory of the structural robustness for flexible cable-bar tensile structure, this paper aimed to conduct further studies. Based on the theory, a fundamental robustness analysis method and a detailed calculation way through the combination of induction of performance criterion and random theory for nonlinear structural robustness quantitative evaluation method were proposed. Following this, a real Geiger cable dome structure was studied as its research object, and the influences of structural robustness of simultaneous changes of all elements section and changes of every kind of element section were analysed, respectively. Finally, the genetic algorithm was applied through MATLAB and ANSYS software to achieve optimal section layout, with the goal of minimizing structural quality on the condition that the structural robustness indicator keep less than that of the initial structure. The result revealed that the increase of the section of elements can effectively enhance structural robustness and the section changes of various elements showed different sensitivities to the influence of structural robustness. Meanwhile, structural quality can be effectively reduced by optimizing measures such as increasing the section of elements with significant effect on structural robustness and reducing the section of elements with minor effects on structural robustness, while the structural robustness indicator keeps less than that of the initial structure. The optimization reveals that quality was reduced by 42.5% in this paper.


2021 ◽  
Vol 26 (1) ◽  
Author(s):  
Kanae Bekki ◽  
Shigehisa Uchiyama ◽  
Yohei Inaba ◽  
Akira Ushiyama

Abstract Background In recent years, heated tobacco products (HTPs), which are widely used in Japan, have been sold by various brands using additives such as flavors. It has been reported that the components of mainstream smoke are different from those of conventional cigarettes. In this study, we established an analytical method for furans and pyridines in the mainstream smoke, which are characteristic of HTPs and particularly harmful among the generated components, and investigated the amount of component to which the smokers are exposed. Methods We established a simple analytical method for simultaneous analysis of gaseous and particulate compounds in the mainstream smoke of HTPs (IQOS, glo, ploom S) in Japan by combining a sorbent cartridge and glass fiber filter (Cambridge filter pad (CFP)). Both the sorbent cartridge and CFP were extracted using 2-propanol and analyzed via GC-MS/MS to determine the concentration of furans and pyridines generated from each HTP. Results The results showed that the levels of target furans such as furfural, 2-furanmethanol, 2(5H)-furanone, and 5-methylfurfural tended to be higher in the mainstream smoke of glo than in standard cigarettes (3R4F). Pyridine, which is generated at a high level in 3R4F as a combustion component, and 4-ethenylpyridine (EP), which is a known marker of environmental tobacco smoke, were detected. Among these components, 2-furanmethanol and pyridine are classified as Group 2B (possibly carcinogenic to humans) by the International Agency for Research on Cancer (IARC). Therefore, it is possible that they will contribute to the health effects caused by use of HTPs. Conclusions Using the new collection and analytical method for furans and pyridines in the mainstream smoke of HTPs, the level of each compound to which smokers are exposed could be clarified. By comprehensively combining information on the amount of ingredients and toxicity, it will be possible to perform a more detailed calculation of the health risks of using HTPs. In addition, the components detected in this study may be the causative substances of indoor pollution through exhaled smoke and sidestream smoke; therefore, environmental research on the chemicals generated from HTPs would be warranted in future studies.


2021 ◽  
Vol 57 (8) ◽  
Author(s):  
Yong-Hui Lin ◽  
Hans-Werner Hammer ◽  
Ulf-G. Meißner

AbstractWe review the dispersion-theoretical analysis of the electromagnetic form factors of the nucleon. We emphasize in particular the role of unitarity and analyticity in the construction of the isoscalar and isovector spectral functions. We present new results on the extraction of the nucleon radii, the electric and magnetic form factors and the extraction of $$\omega $$ ω -meson couplings. All this is supplemented by a detailed calculation of the theoretical uncertainties, using bootstrap and Bayesian methods to pin down the statistical errors, while systematic errors are determined from variations of the spectral functions. We also discuss the physics of the time-like form factors and point out further issues to be addressed in this framework.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Bin Zhu ◽  
Zhaodong Wang ◽  
Lianfang Tian ◽  
Jinmei Guo ◽  
Lingjian Wang ◽  
...  

Dealing with problems of illumination changes in optical flow estimation, an improved variational optical flow model is proposed in this paper. The local structure constancy constraint (LSCC) is applied in the data term of the traditional HS (Horn & Schunck) optical flow model to substitute the brightness constancy constraint. The fractional-order smoothness constraint (FSC) is applied in the smoothness term of the HS model. Then, the detailed calculation processes from the optical flow model to the optical flow value are explained. The structure tensor in LSCC is an image feature that is constant in the illumination changes scene. The fractional differential coefficient in FSC can fuse the local neighborhood optical flow vector into the optical flow vector of the target pixel, which can improve the integrity of the motion region with the same motion speed. Combining LSCC with FSC, our improved optical flow model can obtain an accurate optical flow field with clear outline in the illumination abnormity scene. The experimental results show that, compared with other optical flow models, our model is more suitable for the illumination changes scene and can be employed in outdoor motion detection projects.


Author(s):  
Bertold Damesse ◽  
Francois Damesse ◽  
Roland Kirchberger ◽  
Kevin Wamba ◽  
Markus Sperka

The instability of Cameroon's electricity network leads to recurrent power outages, which constitute a significant obstacle to socio-economic activity in the region [3]. This is also the case for the agricultural activities carried out by the GIC PROSER in the MEYO area of Yaoundé. The main objective of this work is to demonstrate a solution approach for an ecologically sustainable and relatively self-sufficient solar energy supply by GIC-PROSER, thus creating a prototypical model for other farms. For this purpose, a detailed calculation of the annual energy demand was performed. A first investigation was done in order to find out the potential of wind energy, but the wind speeds are not sufficient to provide enough electrical energy due to the location of the farm. Subsequently, a thorough and optimized planning of a solar generator was made, taking into account the solar radiation data of the area. Finally, an approximate of the economic efficiency calculation of this ecological generator was shown. This results in an annual demand of 25,647 kWh/a with a peak load of 12.8 kW. On the roofs of two farm buildings, 49 solar modules with 600 W each are to be installed, resulting in an output of about 29.4 kW. The solar generator (AC grid) provides an annual energy of almost 38,794 kWh. About 32% of this energy is consumed directly by the electrical equipment on the farm. About 55% can be used for battery charging. The annual surplus of produced energy, about 4,131.90 kWh, is fed directly into the grid. This leads to a degree of autonomy of 90%. This solar system costs about 16,000,000 FCFA (24,425 EUR) and it is amortized 11 years after its installation.  


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