scholarly journals A longitudinal analysis of collapsibility with predictions over the southeastern Loess Plateau in China

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ziyu Zheng ◽  
Xi-an Li ◽  
Li Wang
Keyword(s):  
Loess Plateau ◽  
Structural Parameters ◽  
Experimental Studies ◽  
Spatial Modelling ◽  
Influential Factors ◽  
Severe Accidents ◽  
Novel Approach ◽  
Porosity Ratio ◽  
Increasing Demand ◽  
Representative Area

AbstractLoess presents very unique collapsible behaviour due to its special under-compactness, weak cementation and porousness. Many environmental issues and geological hazards including subgrade subsidences, slope collapses or failures, building cracking and so on are directly caused by the collapsible deformation of loess. Such collapsible behaviour may also severe accidents due to sinkholes, underground caves or loess gullies. Moreover, with the increasing demand of construction and development in the loess areas, an in-depth research towards effective evaluation of loess collapsibility is urged. Currently no studies have made attempts to explore a rather complete and representative area of Loess Plateau. This paper thus provides a novel approach on spatial modelling over Jin-Shan Loess Plateau as an extension to experimental studies. The in-lab experiment results have shown that shown that the porosity ratio and collapsibility follow a Gaussian distribution and a Gamma distribution respectively for both sampling areas: Yan’an and Lv Liang. This establishes the prior intuition towards spatial modelling which provides insights of potential influential factors on loess collapsibility and further sets a potential direction of the loess studies by considering an extra dimension of spatial correlation. Such modelling allows robust predictions taken into account of longitudinal information as well as structural parameters and basic physical properties. Water contents, dry densities, pressure levels and elevations of samples are determined to be statistically significant factors which affect the loess collapsibility. All regions in Lv Liang area are at risk of high collapsibility with average around 0.03, out of which roughly a third of them are predicted to be at high risk. Clear spatial patterns of higher expected collapsibility in the southwest comparing to the northeast are shown adjusting for influential covariates. On reference guidelines for potential policy makings, county-level regions with the highest expected loess collapsibility are also identified.

scholarly journals Estimating Changes in the Green Water Productivity of Cropping Systems in Northern Shaanxi Province in China’s Loess Plateau

Water ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 1198 ◽  
Author(s):  
Jinping Wang ◽  
Jinzhu Ma ◽  
Afton Clarke-Sather ◽  
Jiansheng Qu
Keyword(s):  
Loess Plateau ◽  
Hydrological Modeling ◽  
Meteorological Data ◽  
Water Productivity ◽  
Experimental Studies ◽  
Northern Region ◽  
Green Water ◽  
Shaanxi Province ◽  
Cropping Patterns ◽  
Northern Shaanxi

Water shortages limit agricultural production in the world’s arid and semi-arid regions. The Northern region of China’s Shaanxi Province, in the Loess Plateau, is a good example. Raising the water productivity of rainfed grain production in this region is essential to increase food production and reduce poverty, thereby improving food security. To support efforts to increase crop water productivity (CWP), we accounted for limitations of most existing studies (experimental studies of specific crops or hydrological modeling approaches) by using actual field data derived from statistical reports of cropping patterns. We estimated the CWPs of nine primary crops grown in four counties in Northern Shaanxi from 1994 to 2008 by combining statistics on the cultivated area and yields with detailed estimates of evapotranspiration based on daily meteorological data. We further calculated both the caloric CWP of water (CCWP) and the CWP of productive water (i.e., water used for transpiration). We found that regional CWP averaged 6.333 kg mm–1 ha–1, the CCWP was 17,683.81 cal mm–1 ha–1, the CWP of productive green water was 8.837 kg mm–1 ha–1, and the CCWP of productive green water was 24,769.07 cal mm–1 ha–1. Corn, sorghum, and buckwheat had the highest CWP, and although potatoes had the largest planted area and relatively high CWP, they had a low CCWP.

Prioritizing strain insulators for raptor conservation

2021 ◽  
pp. 1-16
Author(s):  
FRANCISCO GUIL ◽  
M. ÁNGELES SORIA ◽  
VÍCTOR ORTEGA ◽  
RUBÉN GARCÍA-SÁNCHEZ ◽  
SILVIA VILLAVERDE-MORCILLO
Keyword(s):  
Methodological Approach ◽  
Risk Index ◽  
Influential Factors ◽  
Negative Effects ◽  
Central Spain ◽  
Novel Approach ◽  
Conservation Actions ◽  
Complete Survey ◽  
Raptor Conservation ◽  
Management And Conservation

Summary Avian species often take advantage of human-made structures, such as perching on power poles, although this can lead to negative effects for both birds and infrastructure. It has been demonstrated that anchor-type pylons, with strain insulators, are amongst the most dangerous of these structures. Our goal was to develop a methodological approach to evaluate the ways in which raptors perch on the six most commonly used strain insulator configurations in Spain, and to build a risk index that can be used to prioritise them. To study the ways raptors perch, we worked with six wildlife rescue centres in central Spain for almost a year assessing these six strain insulator configurations in 83 perch trials with 176 raptors in ample flying pens. We analysed 475 complete survey days, with an approximate number of 258,960 analysed pictures, including 6,766 perchings on strain insulators. We assessed the influential factors for these 6,766 perchings and developed a novel approach to prioritise strain insulator configurations that can be used anywhere. Our results suggest that longer insulator strains (i.e. PECA-1000 and Caon-C3670) are the safest, according to our prioritization criteria, although these results require further assessment in the field. Managers and conservationists should take into account these results to improve management and conservation actions.

scholarly journals Human emotion modeling (HEM): an interface for IoT systems

2021 ◽  
Author(s):  
Mohammed R. Elkobaisi ◽  
Fadi Al Machot
Keyword(s):  
Assisted Living ◽  
High Performance ◽  
Modeling Language ◽  
Emotional States ◽  
Human Emotion ◽  
Care Givers ◽  
Novel Approach ◽  
Domain Specific Modeling ◽  
Increasing Demand ◽  
Human Support

AbstractThe use of IoT-based Emotion Recognition (ER) systems is in increasing demand in many domains such as active and assisted living (AAL), health care and industry. Combining the emotion and the context in a unified system could enhance the human support scope, but it is currently a challenging task due to the lack of a common interface that is capable to provide such a combination. In this sense, we aim at providing a novel approach based on a modeling language that can be used even by care-givers or non-experts to model human emotion w.r.t. context for human support services. The proposed modeling approach is based on Domain-Specific Modeling Language (DSML) which helps to integrate different IoT data sources in AAL environment. Consequently, it provides a conceptual support level related to the current emotional states of the observed subject. For the evaluation, we show the evaluation of the well-validated System Usability Score (SUS) to prove that the proposed modeling language achieves high performance in terms of usability and learn-ability metrics. Furthermore, we evaluate the performance at runtime of the model instantiation by measuring the execution time using well-known IoT services.

scholarly journals Pros and Cons of the Cannabinoid System in Cancer: Focus on Hematological Malignancies

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3866
Author(s):  
Natasha Irrera ◽  
Alessandra Bitto ◽  
Emanuela Sant’Antonio ◽  
Rita Lauro ◽  
Caterina Musolino ◽  
...  
Keyword(s):  
Cannabinoid Receptors ◽  
Hematological Malignancies ◽  
Antitumor Agents ◽  
Control Cell ◽  
Experimental Studies ◽  
Endocannabinoid System ◽  
Chemotherapeutic Agents ◽  
Cancer Cell Growth ◽  
Cell Functions ◽  
Novel Approach

The endocannabinoid system (ECS) is a composite cell-signaling system that allows endogenous cannabinoid ligands to control cell functions through the interaction with cannabinoid receptors. Modifications of the ECS might contribute to the pathogenesis of different diseases, including cancers. However, the use of these compounds as antitumor agents remains debatable. Pre-clinical experimental studies have shown that cannabinoids (CBs) might be effective for the treatment of hematological malignancies, such as leukemia and lymphoma. Specifically, CBs may activate programmed cell death mechanisms, thus blocking cancer cell growth, and may modulate both autophagy and angiogenesis. Therefore, CBs may have significant anti-tumor effects in hematologic diseases and may synergistically act with chemotherapeutic agents, possibly also reducing chemoresistance. Moreover, targeting ECS might be considered as a novel approach for the management of graft versus host disease, thus reducing some symptoms such as anorexia, cachexia, fatigue, anxiety, depression, and neuropathic pain. The aim of the present review is to collect the state of the art of CBs effects on hematological tumors, thus focusing on the essential topics that might be useful before moving into the clinical practice.

Hypoxic mechanisms in primary headaches

Cephalalgia ◽  
2016 ◽  
Vol 37 (4) ◽  
pp. 372-384 ◽  
Author(s):  
Josefine Britze ◽  
Nanna Arngrim ◽  
Henrik Winther Schytz ◽  
Messoud Ashina
Keyword(s):  
Cluster Headache ◽  
High Altitude ◽  
Acute Mountain Sickness ◽  
Experimental Studies ◽  
Epidemiological Studies ◽  
Primary Headaches ◽  
Secondary Headaches ◽  
Novel Approach ◽  
Calcitonin Gene ◽  
Level Of Knowledge

Background Hypoxia causes secondary headaches such as high-altitude headache (HAH) and headache due to acute mountain sickness. These secondary headaches mimic primary headaches such as migraine, which suggests a common link. We review and discuss the possible role of hypoxia in migraine and cluster headache. Methods This narrative review investigates the current level of knowledge on the relation of hypoxia in migraine and cluster headache based on epidemiological and experimental studies. Findings Epidemiological studies suggest that living in high-altitude areas increases the risk of migraine and especially migraine with aura. Human provocation models show that hypoxia provokes migraine with and without aura, whereas cluster headache has not been reliably induced by hypoxia. Possible pathophysiological mechanisms include hypoxia-induced release of nitric oxide and calcitonin gene-related peptide, cortical spreading depression and leakage of the blood-brain barrier. Conclusion There is a possible link between hypoxia and migraine and maybe cluster headache, but the exact mechanism is currently unknown. Provocation models of hypoxia have yielded interesting results suggesting a novel approach to study in depth the mechanism underlying hypoxia and primary headaches.

Effect of Temperature, Reeling Speed and Pipe Tension on the Performance of Field Joint Coating During Reeling of Offshore Pipelines

2021 ◽  
Author(s):  
Rajaram Dhole ◽  
Ismael Ripoll ◽  
Sabesan Rajaratnam ◽  
Celine Jablonski
Keyword(s):  
Influential Factors ◽  
Influential Factor ◽  
Effect Of Temperature ◽  
Mechanical And Thermal Properties ◽  
Peak Strain ◽  
Element Analysis ◽  
Novel Approach ◽  
Laboratory Test Results ◽  
Coating Design ◽  
Highly Strained

Abstract Pipelines are coated with insulating material that minimizes heat losses to the environment. Reeled pipe can experience nominal bending strain in the order of 1% to 2%. Thick coating on the pipe is inherently more highly strained, because of concentrations that occur at the interface between parent coating and field joint coating. Occasionally, contractors who specialize in pipe-lay using the reeling method have experienced difficulties relating to unexpected disbondment and cracks in coating at these interfaces. Any disbonded coating is routinely identified and repaired, but it is important to understand the influential factors that could lead to this type of coating disbondment. It is known in the industry that parameters such as temperature, reeling speed and pipe tension are influential but the relative influence of the factors is not well understood. In addition, there is currently no industry code or recommended practice that proposes the strain levels that the coating could safely withstand prior to cracking. This paper addresses thermo-mechanical aspects of coating design and presents a novel approach to quantify which parameters have the largest influence. In the presented assessments, coating strain was assessed using finite element analysis. Material input was selected from a combination of typical values and specific laboratory test results for polypropylene (PP) and injection molded polypropylene (IMPP). An essential aspect was that the mechanical and thermal properties of the PP were related to temperature and strain rate. Strain rates in the coating during reeling operations were obtained from global FE models. Detailed local FE models incorporated all the material and load inputs and temperature conditions that are necessary to determine peak strain values in the coating; the peak strain values would indicate the locations of potential coating disbondment. The study is purely a strain assessment and excludes any potential for defects or delamination in the coating that could result from its manufacturing process. This strain-based study revealed that coating temperature during reeling is the most influential factor on strain level in the coating. Reeling speed and pipe tension are parameters providing secondary influences.

scholarly journals A structural approach to control of transitional waves of nonlinear diffusion-reaction systems: Theory and possible applications to bio-medicine

2002 ◽  
Vol 7 (1) ◽  
pp. 27-40 ◽  
Author(s):  
Victor Kardashov ◽  
Shmuel Einav
Keyword(s):  
Nonlinear Diffusion ◽  
Structural Parameters ◽  
Deterministic Chaos ◽  
Reaction Diffusion ◽  
Diffusion Reaction ◽  
Reaction Diffusion Systems ◽  
Diffusion Systems ◽  
Novel Approach ◽  
Dynamics Models ◽  
And Control

This paper has considered a novel approach to structural recognition and control of nonlinear reaction-diffusion systems (systems with density dependent diffusion). The main consistence of the approach is interactive variation of the nonlinear diffusion and sources structural parameters that allows to implement a qualitative control and recognition of transitional system conditions (transients). The method of inverse solutions construction allows formulating the new analytic conditions of compactness and periodicity of the transients that is also available for nonintegrated systems. On the other hand, using of energy conservations laws, allows transfer to nonlinear dynamics models that gives the possiblity to apply the modern deterministic chaos theory (particularly the Feigenboum's universal constants and scenario of chaotic transitions).

A Multi-State Strategy for Structural Damage Detection Using Sensitivity of Weighted Transmissibility Function

2021 ◽  
pp. 2150144
Author(s):  
Ziwei Luo ◽  
Huanlin Liu ◽  
Ling Yu
Keyword(s):  
Damage Detection ◽  
Structural Damage ◽  
Model Updating ◽  
Structural Parameters ◽  
Experimental Studies ◽  
Fe Model ◽  
Limited Information ◽  
Structural Damage Detection ◽  
State Strategy ◽  
Output Only

In practice, a model-based structural damage detection (SDD) method is helpful for locating and quantifying damages with the aid of reasonable finite element (FE) model. However, only limited information in single or two structural states is often used for model updating in existing studies, which is not reasonable enough to represent real structures. Meanwhile, as an output-only damage indicator, transmissibility function (TF) is proven to be effective for SDD, but it is not sensitive enough to change in structural parameters. Therefore, a multi-state strategy based on weighted TF (WTF) is proposed to improve sensitivity of TF to change in parameters and in order to further obtain a more reasonable FE model for SDD in this study. First, WTF is defined by TF weighted with element stiffness matrix, and relationships between WTFs and change in structural parameters are established based on sensitivity analysis. Then, a multi-state strategy is proposed to obtain multiple structural states, which is used to reasonably update the FE model and detect structural damages. Meanwhile, due to fabrication errors, a two-stage scheme is adopted to reduce the global and local discrepancy between the real structure and the FE model. Further, the [Formula: see text]-norm and the [Formula: see text]-norm regularization techniques are, respectively, introduced for both model updating and SDD problems by considering the characteristics of problems. Finally, the effectiveness of the proposed method is verified by a simply supported beam in numerical simulations and a six-storey frame in laboratory. From the simulation results, it can be seen that the sensitivity to structural damages can be improved by the definition of WTF. For the experimental studies, compared with the FE model updated from the single structural state, the FE model obtained by the multi-state strategy has an ability to more reasonably describe the change of states in the frame. Moreover, for the given structural damages, the proposed method can detect damage locations and degrees accurately, which shows the validity of the proposed method and the reliability of the updated FE model.

Heterogeneous Meshed Wireless Back-Haul Network Integrating Unidirectional Technologies

2011 ◽  
pp. 139-160 ◽  
Author(s):  
Mathias Kretschmer ◽  
Christian Niephaus ◽  
George Ghinea
Keyword(s):  
Traffic Engineering ◽  
Mesh Networks ◽  
Mobile Adhoc Network ◽  
Wireless Mesh ◽  
Novel Approach ◽  
Triple Play ◽  
High Bandwidth ◽  
Single Radio ◽  
Increasing Demand ◽  
Technology Level

Wireless Mesh Networks (WMNs) have matured in recent years and the visibility of WMN deployments has attracted commercial operators to investigate this technology for applicability in their networks. Having their roots in the Mobile Adhoc Network (MANET) world and rather cheap off-the-shelf single-radio WLAN routers, WMN routing protocols were not designed for applicability in carrier-grade back-haul networks. For example, protocols such as OLSR or B.A.T.M.A.N. can not address the QoS-requirements of a modern operator back-haul network with its increasing demand for triple-play content. Although numerous solutions have been proposed to introduce QoS-awareness at the protocol or the technology level, traditional WMNs fail to meet commercial operator requirements in terms of reliability, traffic engineering and QoS guarantees. This chapter proposes a novel approach combining an IEEE 802.21-based control plane and an MPLS-based data plane. To provide support for ubiquitous high-bandwidth multi-media services, it seamlessly integrates unidirectional broadcast technologies such as DVB into the heterogeneous multi-radio WiBACK architecture.

Theoretical and Experimental Studies of Internal Cuttings Removal Bit

2020 ◽  
Vol 143 (4) ◽  
Author(s):  
Tong Cao ◽  
Kaian Yu ◽  
Wenxing Li ◽  
Xuyue Chen ◽  
Hongwu Zhu
Keyword(s):  
Oil And Gas ◽  
Drilling Fluid ◽  
Structural Parameters ◽  
Cone Angle ◽  
Experimental Studies ◽  
Polycrystalline Diamond ◽  
Screw Conveyor ◽  
Rotating Speed ◽  
Positive Effects ◽  
Two Samples

Abstract The oil and gas exploration without rig (also known as badger exploration) is a novel exploration technology that removes the need for fixed rig drilling, bringing with it the promise of huge savings in terms of time and money and its low impact on the environment. The implementation of this technology is an autonomous exploration tool, which can drill into rock using an electrically powered bit to loosen and crush the formation ahead of it, and crushed cuttings is moved through the device and deposited in the space behind it. Because there is no drilling fluid in badger drilling, a new way of transporting cuttings is urgently needed. In this paper, a new kind of bit named internal cuttings removal (ICR) bit is developed for badger exploration, and it can not only drill rock but also collect and transport cuttings to the bit behind through the inner cavity of the bit. Compared with the common polycrystalline diamond compact (PDC) bit, the junk slots are removed, but the helical blades and screw conveyor are added on the ICR bit. Theoretically, the two effects of rotating helical blades on cuttings moving are studied, based on the conditions of low and high rotating speed, respectively. Moreover, the rate of cuttings removal of the ICR bit is given in formulas, and in order to ensure the cuttings is removed from bottomhole timely, and the maximum permissible rate of penetration (ROP) of the ICR bit is proposed. Finally, two samples of the ICR bit with different structural parameters were built and tested in dry and wet rock drilling experiments, and experimental results show that the ICR bit can achieve the expected goal of ICR, but wet cuttings has a significant influence on the performance of the ICR bit. By comparing the drilling results of two bits, it can be found that the concave blade surface, a small number of blades, and small inner cone angle have the positive effects on the cuttings removal of the ICR bit. The above work is helpful for the development and implementation of badger exploration technology.

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