scholarly journals Effects of Colloidal Silica Grouting on Geotechnical Properties of Liquefiable Soils: A Review

Geotechnics ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 460-491
Author(s):  
Giovanni Ciardi ◽  
Giovanni Vannucchi ◽  
Claudia Madiai
Keyword(s):  
Colloidal Silica ◽  
Soil Layer ◽  
Soil Improvement ◽  
Critical Discussion ◽  
Future Research ◽  
Soil Behavior ◽  
Cohesionless Soils ◽  
Seismic Liquefaction ◽  
Physical Model Tests ◽  
Strength And Stiffness

Colloidal silica (CS) is a kind of nanomaterial used in soil/rock grouting techniques in different branches of civil engineering. Many studies have recently been performed to investigate the potential of CS in improving the mechanical behavior of cohesionless soils and mitigating the risk of seismic liquefaction in urbanized areas. CS grout is chemically and biologically inert and, when injected into a subsoil, it can form a silica gel and stabilize the desired soil layer, thus representing an attractive, environmentally friendly alternative to standard chemical grouting techniques. This paper firstly describes the characteristics of CS grout, the gelation process and the main features of the behavior of the pure gelled material. The grout delivery mechanisms through porous media are then explained, pointing out the crucial issues for practical application of CS grouting. All the grouting-induced effects on the soil behavior, which have been investigated by laboratory tests on small-sized soil elements, are reviewed, including the modifications to soil strength and stiffness under both static and seismic loading conditions, to soil compressibility and hydraulic conductivity. Published results from physical model tests and in situ applications are also presented. Finally, some aspects related to the mechanism of soil improvement are discussed. A critical discussion of each topic is presented, drawing particular attention to the controversial or not yet fully examined aspects to which future research on colloidal silica grouting should be directed.

Experimental Study on the Modulus of Subgrade Reaction for Sandy Soil Improved by Grouting Materials

2020 ◽  
Vol 857 ◽  
pp. 358-366
Author(s):  
Mustafa A. Alafeena ◽  
Ala Nasir Aljorany
Keyword(s):  
Colloidal Silica ◽  
Soil Improvement ◽  
Load Test ◽  
Subgrade Reaction ◽  
Plate Load Test ◽  
Modulus Of Subgrade Reaction ◽  
Plate Size ◽  
Strength And Stiffness ◽  
Particulate Soil ◽  
Grouting Materials

Many methods have been used for soil improvement at site, one of these methods is grouting. Cement grouted soils consist of particulate soil media and cementation agents. Such soils have been widely used to improve the shear strength and stiffness of weak soils and for preventing of water seepage through soils. The modulus of subgrade reaction may give a good indication about the soil bearing capacity and stiffness. This geotechnical parameter can be measured by using the plate load test. In this study, an experimental work is done to assess the improvement in the stiffness of sandy soils by injection two different cementing agents (cement and colloidal silica). The work includes plate loading tests with two different plate diameters (B= 150 and B= 250 mm). The effects of plate size, depth of the grouted zone (0-B and B-2B) as well as the effect of grouting material type on the performance of the grouted soil are investigated. The results show that the colloidal silica grout is more effective in increasing the modulus of sub grade reaction (ks) than the cement grout. Also, the use of plate with 150 mm diameter gives higher value of (ks) than that of 250 mm diameter. Furthermore, grout injection at depth (from 0 to B) gives a higher value of (ks) than that for deeper grouted zone.

Amruthapala (Decalepis arayalpathra (J. Joseph and V. Chandras.) Venter): A Comprehensive Review on Diversity, Therapeutic Uses, and Valorization of Bioactive Constituents

2019 ◽  
Vol 20 (5) ◽  
pp. 376-389 ◽  
Author(s):  
Sonali Mishra ◽  
Nupur Srivastava ◽  
Velusamy Sundaresan ◽  
Karuna Shanker
Keyword(s):  
Secondary Metabolite ◽  
Current Knowledge ◽  
Experimental Studies ◽  
Critical Discussion ◽  
Future Research ◽  
Bioactive Constituents ◽  
Medicinal Uses ◽  
Comprehensive Review ◽  
Therapeutic Uses ◽  
Decalepis Arayalpathra

Background: Decalepis arayalpathra (J. Joseph and V. Chandras.) Venter is used primarily for nutrition besides its therapeutic values. Traditional preparations/formulations from its tuber are used as a vitalizer and blood purifier drink. The folklore medicinal uses cover inflammation, cough, wound healing, antipyretic, and digestive system management. A comprehensive review of the current understanding of the plant is required due to emerging concerns over its safety and efficacy. Objective: The systematic collection of the authentic information from different sources with the critical discussion is summarised in order to address various issues related to botanical identity, therapeutic medicine, nutritional usage, phytochemical, and pharmacological potentials of the D. arayalpathra. Current use of traditional systems of medicine can be used to expand future research opportunities. Materials and Methods: Available scripted information was collected manually, from peered review research papers and international databases viz. Science Direct, Google Scholar, SciFinder, Scopus, etc. The unpublished resources which were not available in database were collected through the classical books of ‘Ayurveda’ and ‘Siddha’ published in regional languages. The information from books, Ph.D. and MSc dissertations, conference papers and government reports were also collected. We thoroughly screened the scripted information of classical books, titles, abstracts, reports, and full-texts of the journals to establish the reliability of the content. Results: Tuber bearing vanilla like signature flavor is due to the presence of 2-hydroxy-4-methoxybenzaldehyde (HMB). Among five other species, Decalepis arayalpathra (DA) has come under the ‘critically endangered’ category, due to over-exploitation for traditional, therapeutic and cool drink use. The experimental studies proved that it possesses gastro-protective, anti-tumor, and antiinflammatory activities. Some efforts were also made to develop better therapeutics by logical modifications in 2-Hydroxy-4-methoxy-benzaldehyde, which is a major secondary metabolite of D. arayalpathra. ‘Amruthapala’ offers the enormous opportunity to develop herbal drink with health benefits like gastro-protective, anti-oxidant and anti-inflammatory actions. Results: The plant has the potential to generate the investigational new lead (IND) based on its major secondary metabolite i.e. 2-Hydroxy-4-methoxy-benzaldehyde. The present mini-review summarizes the current knowledge on Decalepis arayalpathra, covering its phytochemical diversity, biological potentials, strategies for its conservation, and intellectual property rights (IPR) status. Chemical Compounds: 2-hydroxy-4-methoxybenzaldehyde (Pubchem CID: 69600), α-amyrin acetate (Pubchem CID: 293754), Magnificol (Pubchem CID: 44575983), β-sitosterol (Pubchem CID: 222284), 3-hydroxy-p-anisaldehyde (Pubchem CID: 12127), Naringenin (Pubchem CID: 932), Kaempferol (Pubchem CID: 5280863), Aromadendrin (Pubchem CID: 122850), 3-methoxy-1,2-cyclopentanedione (Pubchem CID: 61209), p-anisaldehyde (Pubchem CID: 31244), Menthyl acetate (Pubchem CID: 27867), Benzaldehyde (Pubchem CID: 240), p-cymene (Pubchem CID: 7463), Salicylaldehyde (Pubchem CID: 6998), 10-epi-γ-eudesmol (Pubchem CID: 6430754), α -amyrin (Pubchem CID: 225688), 3-hydroxy-4-methoxy benzaldehyde (Pubchem CID: 12127).

scholarly journals A Review of Monitoring Technologies for Solar PV Systems Using Data Processing Modules and Transmission Protocols: Progress, Challenges and Prospects

2021 ◽  
Vol 13 (15) ◽  
pp. 8120
Author(s):  
Shaheer Ansari ◽  
Afida Ayob ◽  
Molla S. Hossain Lipu ◽  
Mohamad Hanif Md Saad ◽  
Aini Hussain
Keyword(s):  
Data Processing ◽  
Data Transmission ◽  
Performance Enhancement ◽  
Critical Discussion ◽  
Signal Interference ◽  
Future Research ◽  
Transmission Protocol ◽  
Range Data ◽  
Solar Pv ◽  
Monitoring Technologies

Solar photovoltaic (PV) is one of the prominent sustainable energy sources which shares a greater percentage of the energy generated from renewable resources. As the need for solar energy has risen tremendously in the last few decades, monitoring technologies have received considerable attention in relation to performance enhancement. Recently, the solar PV monitoring system has been integrated with a wireless platform that comprises data acquisition from various sensors and nodes through wireless data transmission. However, several issues could affect the performance of solar PV monitoring, such as large data management, signal interference, long-range data transmission, and security. Therefore, this paper comprehensively reviews the progress of several solar PV-based monitoring technologies focusing on various data processing modules and data transmission protocols. Each module and transmission protocol-based monitoring technology is investigated with regard to type, design, implementations, specifications, and limitations. The critical discussion and analysis are carried out with respect to configurations, parameters monitored, software, platform, achievements, and suggestions. Moreover, various key issues and challenges are explored to identify the existing research gaps. Finally, this review delivers selective proposals for future research works. All the highlighted insights of this review will hopefully lead to increased efforts toward the enhancement of the monitoring technologies in future sustainable solar PV applications.

scholarly journals Recognition and Work in the Platform Economy: a Normative Reconstruction

2021 ◽  
Author(s):  
Max Visser ◽  
Thomas C. Arnold
Keyword(s):  
Working Conditions ◽  
Critical Discussion ◽  
Future Research ◽  
The Past ◽  
Recognition Theory ◽  
Normative Reconstruction ◽  
Human Side ◽  
Platform Economy

AbstractThe rise of the platform economy in the past two decades (and neoliberal capitalist expansion and crises more in general), have on the whole negatively affected working conditions, leading to growing concerns about the “human side” of organizations. To address these concerns, the purpose of this paper is to apply Axel Honneth’s recognition theory and method of normative reconstruction to working conditions in the platform economy. The paper concludes that the ways in which platform organizations function constitutes a normative paradox, promising flexibility and autonomy while at the same time creating working conditions that undercut these promises. The paper ends with a critical discussion of Honneth’s approach, possible supplementing ideas and further lines of future research.

scholarly journals Social Information Retrieval and Recommendation: state- of-the-art and future research

2019 ◽  
Vol Volume 27 - 2017 - Special... ◽  
Author(s):  
Abir Gorrab ◽  
Ferihane Kboubi ◽  
Henda Ghézala
Keyword(s):  
Information Retrieval ◽  
Web 2.0 ◽  
Social Information ◽  
User Profile ◽  
Critical Discussion ◽  
Social Dimension ◽  
Future Research ◽  
Social Recommendation ◽  
The Social ◽  
Source Of Information

The explosion of web 2.0 and social networks has created an enormous and rewarding source of information that has motivated researchers in different fields to exploit it. Our work revolves around the issue of access and identification of social information and their use in building a user profile enriched with a social dimension, and operating in a process of personalization and recommendation. We study several approaches of Social IR (Information Retrieval), distinguished by the type of incorporated social information. We also study various social recommendation approaches classified by the type of recommendation. We then present a study of techniques for modeling the social user profile dimension, followed by a critical discussion. Thus, we propose our social recommendation approach integrating an advanced social user profile model. L’explosion du web 2.0 et des réseaux sociaux a crée une source d’information énorme et enrichissante qui a motivé les chercheurs dans différents domaines à l’exploiter. Notre travail s’articule autour de la problématique d’accès et d’identification des informations sociales et leur exploitation dans la construction d’un profil utilisateur enrichi d’une dimension sociale, et son exploitation dans un processus de personnalisation et de recommandation. Nous étudions différentes approches sociales de RI (Recherche d’Information), distinguées par le type d’informations sociales incorporées. Nous étudions également diverses approches de recommandation sociale classées par le type de recommandation. Nous exposons ensuite une étude des techniques de modélisation de la dimension sociale du profil utilisateur, suivie par une discussion critique. Ainsi, nous présentons notre approche de recommandation sociale proposée intégrant un modèle avancé de profil utilisateur social.

Investigation of the effects of silicone emulsions having different particle sizes on knitted fabrics depending on the type of yarn

2017 ◽  
Vol 29 (3) ◽  
pp. 394-416 ◽  
Author(s):  
Burcu Sancar Besen ◽  
Onur Balci
Keyword(s):  
Future Research ◽  
Particle Sizes ◽  
Knitted Fabrics ◽  
Content Type ◽  
Bursting Strength ◽  
Chemical Structures ◽  
Strength And Stiffness ◽  
Ring Open ◽  
Working Parameters ◽  
Physical And Chemical

Purpose The purpose of this paper is to investigate the effects of silicone-based softeners, which were developed with different particle sizes (nano, micro, and macro) and chemical structures, on the performance of 100 percent cotton fabrics knitted with different type of yarn (ring, open-end, and compact). Design/methodology/approach In the study, the silicone emulsions having expected particle sizes were produced at laboratory conditions. The produced silicone emulsions were applied to knitted fabrics with both padding and exhaust methods at different concentrations. Some characterization tests (particle size and zeta potential) were applied to the silicone emulsions before the applications. After the applications, CIELab values, whiteness and color fastness, hyrophility, abrasion, pilling, bursting strength, and stiffness performances of the samples were tested. The changes of the investigated properties were also examined via ANOVA. Findings According to the results, it was found that the silicone applications caused the CIELab values, whiteness degree, hyrophility, pilling, bursting strength and stiffness performance of the fabrics to change depending on the particle sizes of the emulsions, the yarn type of the fabrics, the application type, and the concentration of the silicone emulsions. When the ANOVA results were examined, it was seen that the types of the yarn and the silicone emulsions were the most effective working parameters on the results. Research limitations/implications Because no additives were added to the produced silicone emulsions, in the future research, they can be developed with the use of some additives. Thus, it can resolve some of the disadvantages of the silicone emulsions on the textiles. Practical implications While applying the silicone softeners to the knitted fabrics, the type of the yarn and the particle sizes of the emulsions must be determined according to each other, in order to obtain enough handle performance without causing negative change on the other important properties of the knitted fabrics. Originality/value When the studies regarding silicone softeners were investigated, it was found that there were no studies about the effect of the silicone softeners having different particle sizes on the physical and chemical structures of the knitted fabrics depending on the type of yarn and some working parameters such as concentration and type of the application.

Ambidextrous leadership: a narrative literature review for theory development and directions for future research

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Dimitrios Kafetzopoulos
Keyword(s):  
Literature Review ◽  
Theory Development ◽  
Critical Discussion ◽  
Leadership Theory ◽  
Future Research ◽  
Research Gaps ◽  
Content Type ◽  
Narrative Literature ◽  
Narrative Literature Review ◽  
Ambidextrous Leadership

PurposeThis study seeks to provide a narrative literature review of existing empirical research, in order to better understand the processes and theory of ambidextrous leadership, as well as its influence on followers, employees and organizations.Design/methodology/approachData from 26 studies were extracted and synthesied providing a critical discussion about the methodological and theoretical aspects of the studies identified in the review.FindingsIt was revealed the attributes for an effective ambidextrous leader, it was presented the recently proposed concept of ambidextrous leadership theory and it was noticed the main criticisms against the findings of the extant ambidextrous leadership literature. It was also identified many research gaps in the literature which in turn can guide academics in the development of ambidextrous leadership.Research limitations/implicationsThe ambidextrous leadership theory represents a novel and unique approach to the domain of leadership for creativity and innovation. It is shared across hierarchical levels throughout the organization. Leaders have a significant effect on employees' behaviors and should determine its applicability to different situations. Organizations require ambidextrous managers who combine flexible, situational and versatile leadership styles developing ever increasingly new and divergent ideas. Many research gaps in the literature were also identified that can guide academics in the development of ambidextrous leadership.Practical implicationsUnderstanding that ambidextrous leadership is required to significantly influence ambidexterity and innovation allows organizations to direct their leadership selection and development.Originality/valueThis review contributes to the ambidextrous leadership literature by creating a holistic picture of where it has been and where it should go.

Knowledge Management in University-Software Industry Collaboration

2021 ◽  
pp. 114-130
Author(s):  
Marcello Chedid ◽  
Leonor Teixeira
Keyword(s):  
Knowledge Management ◽  
Software Industry ◽  
Technological Development ◽  
Critical Discussion ◽  
Future Research ◽  
Industry Collaboration ◽  
Future Research Directions ◽  
Knowledge Intensive Organizations ◽  
Knowledge Intensive ◽  
The University

The university-software industry collaboration relationship has been represented a key resource, to the extent that together they can more easily promote technological development that underpins innovation solutions. Through a literature review, this chapter aims to explore the concepts and the facilitator or inhibitor factors associated with the collaboration relationships between university and software industry, taking knowledge management into account. This chapter is organized as follows. In the first section, the authors briefly introduce university, software industry, and knowledge management. The following section, based on the literature reviewed, provides a critical discussion of the university-software industry collaboration relationship, knowledge management in knowledge intensive organizations or community, and knowledge management in collaboration relationship between these two types of industries. Finally, in the rest of the sections, the authors point to future research directions and conclude.

scholarly journals Multiwavelength Observations of Galactic Winds: Near and Far

2004 ◽  
Vol 217 ◽  
pp. 276-286
Author(s):  
Sylvain Veilleux
Keyword(s):  
High Redshift ◽  
Critical Discussion ◽  
Future Research ◽  
Nearby Star ◽  
Research Directions ◽  
Star Forming ◽  
Galactic Winds ◽  
Future Research Directions ◽  
Formation And Evolution ◽  
High Redshift Universe

This paper provides a critical discussion of the observational evidence for winds in our own Galaxy, in nearby star-forming and active galaxies, and in the high-redshift universe. The implications of galactic winds on the formation and evolution of galaxies and the intergalactic medium are briefly discussed. A number of observational challenges are mentioned to inspire future research directions.

scholarly journals Futuristic Sustainable Energy Management in Smart Environments: A Review of Peak Load Shaving and Demand Response Strategies, Challenges, and Opportunities

2020 ◽  
Vol 12 (14) ◽  
pp. 5561 ◽  
Author(s):  
Bhagya Nathali Silva ◽  
Murad Khan ◽  
Kijun Han
Keyword(s):  
Energy Management ◽  
Demand Response ◽  
Energy Demand ◽  
Management Strategies ◽  
Peak Load ◽  
Critical Discussion ◽  
Future Research ◽  
Smart Environments ◽  
Challenges And Opportunities ◽  
Management Approaches

The emergence of the Internet of Things (IoT) notion pioneered the implementation of various smart environments. Smart environments intelligibly accommodate inhabitants’ requirements. With rapid resource shrinkage, energy management has recently become an essential concern for all smart environments. Energy management aims to assure ecosystem sustainability, while benefiting both consumers and utility providers. Although energy management emerged as a solution that addresses challenges that arise with increasing energy demand and resource deterioration, further evolution and expansion are hindered due to technological, economical, and social barriers. This review aggregates energy management approaches in smart environments and extensively reviews a variety of recent literature reports on peak load shaving and demand response. Significant benefits and challenges of these energy management strategies were identified through the literature survey. Finally, a critical discussion summarizing trends and opportunities is given as a thread for future research.

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