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1 – 10 of 254
Open Access
Article
Publication date: 24 January 2020

Mingyu Zhang, Jing Wang, Peiran Yang, Zhaohua Shang, Yi Liu and Longjie Dai

This paper aims to study the influence of the dimension change of bush-pin on the pressure, oil film thickness, temperature rise and traction coefficient in contact zone by using…

Abstract

Purpose

This paper aims to study the influence of the dimension change of bush-pin on the pressure, oil film thickness, temperature rise and traction coefficient in contact zone by using a thermal elastohydrodynamic lubrication (EHL) model for finite line contact. Concretely, the effects of the equivalent curvature radius of the bush and the pin, and the length of the bush are investigated.

Design/methodology/approach

In this paper, the contact between the bush and pin is simplified as finite line contact. The lubrication state is studied by numerical simulation using steady-state line contact thermal EHL. A constitutive equation Ree–Eyring fluid is used in the calculations.

Findings

It is found that by selecting an optimal equivalent radius of curvature and prolonging the bush length can improve the lubrication state effectively.

Originality/value

Under specific working conditions, there exists an optimal equivalent radius to maximize the minimum oil film thickness in the contact zone. The increase of generatrix length will weaken the stress concentration effect in the rounded corner area at both ends of the bush, which can improve the wear resistance of chain.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-10-2019-0448.

Details

Industrial Lubrication and Tribology, vol. 72 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Open Access
Article
Publication date: 29 November 2018

Fawaz Al-Qahtani

This paper aims to scrutinize and analyze the continuity and change in US foreign policy toward the Gulf region, with a comparison between the George W. Bush and Barack Obama…

8461

Abstract

Purpose

This paper aims to scrutinize and analyze the continuity and change in US foreign policy toward the Gulf region, with a comparison between the George W. Bush and Barack Obama administrations. Also, it explores the nature of the changes in US foreign policy toward the Gulf region to explain the factors that lead to change and when this change occurs. Policymakers were one of the most important factors that led to the occurrence of change in US policy. Therefore, the study also focuses on decision-makers as an engine of change in foreign policy. In this vein, the study seeks to answer the following question: what is the extent of continuity and change in US foreign policy toward the Gulf region under both Bush and Obama administrations?

Design/methodology/approach

The study seeks to answer its research question by using the rational choice approach. This approach explains that foreign policy does not change because of change of leadership. Therefore, this approach is suitable to study the research question.

Findings

The study reached several points of results, the most important of which are as follows: there is continuity within US foreign policy toward the Gulf countries under the two Bush and Obama administrations. Despite the difference of mechanisms of implementing this foreign policy under both administrations, the objectives of the US foreign policy are still constant and continuous. For example, although the events of September led to the occurrence of tensions between the USA and the Gulf region, the repercussions of the events of September were ostensible where the effects were confined to a change in tactical objectives. Also, successive American administrations have recognized the USA’s enduring and salient interests in the Gulf region.

Research limitations/implications

The region is important as a source of US energy supplies as a strategic military base of operations and also as a site of US foreign policy influence through relationship with individual nations such as Saudi Arabia and the smaller states of the Gulf Cooperation Council.

Practical implications

This paper adds to the existing literature which charts the effects of US foreign policy on the Gulf region.

Details

Review of Economics and Political Science, vol. 4 no. 1
Type: Research Article
ISSN: 2631-3561

Keywords

Open Access
Article
Publication date: 3 June 2019

Lutendo Patricia Mathivha, Vuyisile Samuel Thibane and Fhatuwani Nixwell Mudau

The purpose of this paper is to investigate the health and medicinal importance of bush tea (Athrixia phylicoides DC) and special tea (Monsonia burkeana Planch. ex Harv), two of…

1997

Abstract

Purpose

The purpose of this paper is to investigate the health and medicinal importance of bush tea (Athrixia phylicoides DC) and special tea (Monsonia burkeana Planch. ex Harv), two of Southern African indigenous herbal teas.

Design/methodology/approach

The two herbal teas, A. phylicoides and M. burkeana were extracted individually and in combined ratios for analysis. The phenolic content was determined and the different phenolic compounds were identified using thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). The anti-diabetic activity of the teas was determined by evaluating the inhibition of both α-amylase and α-glucosidase in vitro. The anti-proliferative activity was measured on human cervical cancer (HeLa) cell line using the MTT (3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium) assay.

Findings

Gallic acid, chlorogenic acid and quercetin were identified to be present in significant quantities by TLC. The HPLC quantified the presence of catechin (1.567 mg/g) and chlorogenic acid (1.862 mg/g) in special tea while chlorogenic acid (1.288 mg/g) was present in bush tea. Bush tea and special tea expressed significant levels of phenolic content and high antioxidant activities. Special tea (S100) expressed high inhibition of α-amylase, α-glucosidase and HeLa cell line proliferation when compared to bush tea (B100).

Originality/value

Both bush tea and special tea could provide an alternative for treatment and management of both diabetes and cervical cancer. However, future studies are needed to investigate their synergistic effect with a wide range of other commercial herbal teas.

Details

British Food Journal, vol. 121 no. 4
Type: Research Article
ISSN: 0007-070X

Keywords

Open Access
Article
Publication date: 13 July 2020

Dalia Hamed

The purpose of this study is to apply a corpus-assisted analysis of keywords and their collocations in the US presidential discourse from Clinton to Trump to discover the meanings…

3976

Abstract

Purpose

The purpose of this study is to apply a corpus-assisted analysis of keywords and their collocations in the US presidential discourse from Clinton to Trump to discover the meanings of these words and the collocates they have. Keywords are salient words in a corpus whose frequency is unusually high (positive keywords) or low (negative keywords) in comparison with a reference corpus. Collocation is the co-occurrence of words.

Design/methodology/approach

To achieve this purpose, the investigation of keywords and collocations is generated by AntConc, a corpus processing software.

Findings

This analysis leads to shed light on the similarities and/or differences amongst the past four American presidents concerning their key topics. Keyword analysis through keyness makes it evident that Clinton and Obama, being Democrats, demonstrate a clear tendency to improve Americans’ life inside their social sphere. Obama surpasses Clinton as regard foreign affairs. Clinton and Obama’s infrequent subjects have to do with terrorism and immigration. This complies with their condensed focus on social and economic improvements. Bush, a republican, concentrates only on external issues. This is proven by his keywords signifying war against terrorism. Bush’s negative use of words marking cooperative actions conforms to his positive use of words indicating external war. Trump’s positive keywords are about exaggerated descriptions without a defined target. He also shows an unusual frequency in referring to his name and position. His words used with negative keyness refer to reforming programs and external issues. Collocations around each top content keyword clarify the word and harmonize with the presidential orientation negotiated by the keywords.

Research limitations/implications

Limitations have to do with the issue of the accurate representation of the samples.

Originality/value

This research is original in its methodology of applying corpus linguistics tools in the analysis of presidential discourses.

Details

Journal of Humanities and Applied Social Sciences, vol. 3 no. 2
Type: Research Article
ISSN: 2632-279X

Keywords

Open Access
Article
Publication date: 28 February 2023

Dennis Albert, Lukas Daniel Domenig, Philipp Schachinger, Klaus Roppert and Herwig Renner

The purpose of this paper is to investigate the applicability of a direct current (DC) hysteresis measurement on power transformer terminals for the subsequent hysteresis model…

Abstract

Purpose

The purpose of this paper is to investigate the applicability of a direct current (DC) hysteresis measurement on power transformer terminals for the subsequent hysteresis model parametrization in transformer grey box topology models.

Design/methodology/approach

Two transformer topology models with two different hysteresis models are used together with a DC hysteresis measurement via the power transformer terminals to parameterize the hysteresis models by means of an optimization. The calculated current waveform with the derived model in the transformer no-load condition is compared to the measured no-load current waveforms to validate the model.

Findings

The proposed DC hysteresis measurement via the power transformer terminals is suitable to parametrize two hysteresis models implemented in transformer topology models to calculate the no-load current waveforms.

Originality/value

Different approaches for the measurement and utilization of transformer terminal measurements for the hysteresis model parametrization are discussed in literature. The transformer topology models, derived with the presented approach, are able to reproduce the transformer no-load current waveform with acceptable accuracy.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 42 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Open Access
Article
Publication date: 12 July 2022

Ahmed Samir Mahdi

This paper aims to argue that the Global Political Economy (GPE) theory of neomercantilism provides a sound explanation to the American military involvement in the Persian Gulf…

1131

Abstract

Purpose

This paper aims to argue that the Global Political Economy (GPE) theory of neomercantilism provides a sound explanation to the American military involvement in the Persian Gulf. Accordingly, this paper also proposes the concept of “Neomercantilist War” which analyses the use of military force to protect a strategically vital economic resource (such as Gulf oil). Neomercantilist War is a point of similarity between the GPE school of neomercantilism and the International Relations (IR) school of realism.

Design/methodology/approach

The 1991 Gulf War and the American invasion of Iraq in 2003 are two major events of American military involvement to protect and/or seize Gulf oil. These two events will be tested for neomercantilism, in addition to the concept of “Neomercantilist War” as presented in the paper. The first feature, or definitional component, of neomercantilism is the major role of the state, the second is the preponderance of security/geopolitical goals over economic goals and the third is the zero-sum, relative gains mentality to dealing between states IR.

Findings

The GPE school of neomercantilism and the concept of Neomercantilist War do offer a sound explanation of American military involvement in the Gulf.

Originality/value

The American military involvement in the Gulf region has been analysed using the IR schools of realism and liberalism, but never using GPE theory. Even though GPE is mostly concerned with economic activity, the scope of GPE should be expanded to include military policies if they affect economic resources and activity.

Details

Review of Economics and Political Science, vol. 7 no. 4
Type: Research Article
ISSN: 2356-9980

Keywords

Open Access
Article
Publication date: 19 September 2020

Harry Wels

To further develop research methodologies for multi-species ethnographic fieldwork, based on researcher's experiences with multi-species fieldwork in private wildlife…

3809

Abstract

Purpose

To further develop research methodologies for multi-species ethnographic fieldwork, based on researcher's experiences with multi-species fieldwork in private wildlife conservancies in South Africa and inspired by San tracking techniques.

Design/methodology/approach

Reflections on methodological lessons learnt during multi-species ethnographic fieldwork in South Africa. The approach is rather “Maanenesque” in telling various types of tales of the field. These tales also implicitly show how all-encompassing ethnographic fieldwork and its accompanying reflexivity are; there is never time for leisure in ethnographic fieldwork.

Findings

That developing fieldwork methodologies in multi-species ethnographic research confronts researchers with the explicit need for and training in multi-sensory methods and interpretations, inspired by “the art of tracking” of the San.

Originality/value

Comes up with a concrete suggestion for a sequence of research methods for multi-species ethnography based on the trials and tribulations of a multi-species ethnographer's experiences in South Africa and inspired by San tracking techniques.

Details

Journal of Organizational Ethnography, vol. 9 no. 3
Type: Research Article
ISSN: 2046-6749

Keywords

Open Access
Article
Publication date: 9 January 2024

Shetie Gatew and Nura Guyo

The purpose of this study results and recommendations will have a paramount significance for policymakers, policy advocates, development planners and practitioners who may be in…

Abstract

Purpose

The purpose of this study results and recommendations will have a paramount significance for policymakers, policy advocates, development planners and practitioners who may be in need of such information for reconsideration, evaluation and inclusion into their respective development and humanitarian programming and operational strategies. Above all, the study result has further provided the local community with viable adaptation strategies to climate-induced changes in the study area.

Design/methodology/approach

This study was conducted to measure the livelihood vulnerability of Borana pastoralists to climate change and variability in southern Ethiopia. Pastoralists’ households were sampled using multistage sampling techniques. A total of 27 socio-economic and biophysical indicators were used to reflect vulnerability components: adaptive capacity, exposure and sensitivity. Principal component analysis was used to develop weights for indicators and to produce livelihood vulnerability index to classify households according to their level of vulnerability. Ordinal logistic regression was used to identify the determinants of vulnerability to climate-induced stresses.

Findings

The results showed that 24.4% of households were highly vulnerable, 60.3% were moderately vulnerable and 15.3% of households were less vulnerable to climate-induced stresses. Factor estimates of the logistic model further revealed that early warning information, bush encroachment, coping strategy, temperature, drought frequency, provision of humanitarian services and food shortage during the normal season of the year have a significant influence on vulnerability in the study area.

Social implications

The study’s results and recommendations will be of great significance to policymakers, development planners, and practitioners who require such information for reconsideration, evaluation, and inclusion in their respective development and humanitarian program and operational strategies. Most importantly, the study’s findings have provided the local community with practical adaptation strategies to climate-induced changes in the study area.

Originality/value

The study explored pastoralist perception of climate change and variability and measured the livelihood vulnerability of pastoralists’ households to climate change and variability and finally investigated viable adaptation and coping strategies in the study area.

Details

International Journal of Climate Change Strategies and Management, vol. 16 no. 1
Type: Research Article
ISSN: 1756-8692

Keywords

Open Access
Article
Publication date: 21 May 2020

Damian Felladam Tangonyire and George Agana Akuriba

Farmers all over the country have been exposed to various adaptation strategies to climate change. The adaptation options however focus too closely on technical skills and…

4416

Abstract

Purpose

Farmers all over the country have been exposed to various adaptation strategies to climate change. The adaptation options however focus too closely on technical skills and technologies and fail to address critical social factors such as culture, beliefs and values that influence the adoption and effective implementation of new adaptation technologies, skills and capacity. This paper aims to assess the socioeconomic factors influencing farmers’ specific adaptive strategies to climate change in Pwalugu and Balungu communities in the Talensi district of the Upper East Region of Ghana. This study used purposive sampling technique to select the study communities, whereas simple random sampling technique was used to select a total of 100 respondents from the selected communities. Questionnaires, key informant interviews and focus group discussions were used in collecting data from respondents. This study used detailed statistical test to analyze the data, and the results are presented in the form of figures and tables. This study highlights the legal and institutional context which must be adopted for effective response to climate change impacts in rural communities in Northern Ghana. It also recommends that government and relevant stakeholders should collaborate with financial institutions to ensure that funds are readily available to farmers to enable them to effectively adapt to climate change as well as provide training/workshop programs to farmers to enhance their capacity in planning and implementing effective strategies to climate change.

Design/methodology/approach

This study used the integrated methodological approach where quantitative methods were combined with appropriate qualitative methods. According to Sandelowski (2000), this method ensures reliability (the extents to which results are consistent over time) and validity (the means of which measurements are accurate) of the research. A combination of participatory methods, including key informant interviews, household questionnaire surveys and focus-group discussions were used, allowing local people the opportunity to participate by sharing their experiences and knowledge to outline possible solutions to the problem at hand. Multiple methods (Yeasmin and Rahman, 2012) are good at reducing the inadequacies of a single method. Cross-sectional study was used in designing the research. Variables were measured or determined at the same period in a given population. This method allowed the assessment of practices, attitudes, knowledge and beliefs of a population in relation to a particular event or phenomenon (Olsen and George, 2014).

Findings

The findings of this study revealed farming as the major occupation in the two communities with males being dominant. Diverse livelihood activities such as fishing, animal/poultry rearing, firewood/charcoal production, hunting and driving were other activities respondents engaged to earn a living. In terms of institutional arrangements, avoidance of bush burning and tree felling were the norms influencing decision-making in the two communities. Fear of being punished, animals feeding on some of the grasses, trees inducing rainfall as well as benefits respondents get from trees were the reasons these norms were adhered to in the study area. Access to land, gender dynamics and finance were identified as the socioeconomic factors in the study area. High demands by landowners, last minute change of mind by landowners, limited fertile lands, lack of money to acquire lands, behavior of tenants, number of acres required and lands far from water bodies were the challenges associated with acquiring land in the communities. Access to finance influenced respondents’ ability to acquire fertile lands, lands closer to water bodies and any number of acres of their choice. Gender however impeded women adaptation strategies to climate change. Women were not allowed to own land and other property in the form of animals simply because they are seen as migrants and they do not know the history of the land.

Originality/value

This is a master’s thesis project. This paper shows the socioeconomic factors, which are influencing farmers’ specific adaptation to climate change in the Talensi district of Ghana.

Details

Ecofeminism and Climate Change, vol. 2 no. 2
Type: Research Article
ISSN: 2633-4062

Keywords

Open Access
Article
Publication date: 19 September 2023

Mohamad Zreik

This paper aims to examine the USA's policy toward Myanmar or Burma, analyzing the bilateral relationship between the two countries from the pre-colonial period to the present…

Abstract

Purpose

This paper aims to examine the USA's policy toward Myanmar or Burma, analyzing the bilateral relationship between the two countries from the pre-colonial period to the present day. It highlights the implications of political shifts in the system of government in Myanmar for the bilateral relationship with the USA, particularly after the 1962 coup and the emergence of rising regional powers like China. The paper also shows how the economic role of Myanmar has increased, leading to more equal relations with the United States of America.

Design/methodology/approach

This paper employs a qualitative research design, analyzing data from both primary and secondary sources. The methodology includes a literature review and document analysis to gain a comprehensive understanding of the USA–Myanmar bilateral relationship. The research also analyzes political and economic developments in Myanmar and the region, placing the USA policy in a broader context.

Findings

The research finds that the USA has been an influential player in Myanmar's politics and economy. However, with Myanmar's integration into the Chinese Belt and Road Initiative and its accession to Association of Southeast Asian Nations (ASEAN), its economic role has become more significant, leading to a more balanced relationship with the USA. The paper also shows that the USA's policy toward Myanmar has undergone significant changes, particularly after the 2011 easing of sanctions by former President Barack Obama.

Originality/value

Although many works have traced the history of USA–Myanmar ties, this study provides a fresh perspective by setting past events against the backdrop of contemporary geopolitical upheavals, therefore highlighting the complex evolution of their bilateral dynamics. The paper contributes to the literature on the USA–Myanmar bilateral relationship by providing a comprehensive analysis of the relationship from a historical perspective. The research also adds to the discussion of the implications of political and economic developments in Myanmar for the bilateral relationship with the USA. The findings of this study have important implications for policymakers and scholars interested in the USA's role in Southeast Asia and its relations with rising regional powers like China.

Details

Southeast Asia: A Multidisciplinary Journal, vol. 23 no. 3
Type: Research Article
ISSN: 1819-5091

Keywords

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