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1 – 10 of over 1000Yanli Zhai, Gege Luo and Dang Luo
The purpose of this paper is to construct a grey incidence model for panel data that can reflect the incidence direction and degree between indicators.
Abstract
Purpose
The purpose of this paper is to construct a grey incidence model for panel data that can reflect the incidence direction and degree between indicators.
Design/methodology/approach
Firstly, this paper introduces the concept of a negative matrix and preprocesses the data of each indicator matrix to eliminate differences in dimensions and magnitudes between indicators. Then a model is constructed to measure the incidence direction and degree between indicators, and the properties of the model are studied. Finally, the model is applied to a practical problem.
Findings
The grey-directed incidence degree is 1 if and only if corresponding elements between the feature indicator matrix and the factor indicator matrix have a positive linear relationship. This degree is −1 if and only if corresponding elements between the feature indicator matrix and the factor indicator matrix have a negative linear relationship.
Practical implications
The example shows the number of days with good air quality is negatively correlated with the annual average concentration of each pollutant index. PM2.5, PM10 and O3 are the main pollutants affecting air quality in northern Henan.
Originality/value
This paper introduces the negative matrix and constructs a model from the holistic perspective to measure the incidence direction and level between indicators. This model can effectively measure the incidence between the feature indicator and factor indicator by integrating information from the point, row, column and matrix.
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Keywords
This paper sets out to solve a common and crucial fundamental theoretical problem of gray incidence cluster analysis: to
Abstract
Purpose
This paper sets out to solve a common and crucial fundamental theoretical problem of gray incidence cluster analysis: to
Design/methodology/approach
This paper does not study the concrete expressions of various incidence degrees but rather the perfect correlation essence of such incidence degrees, that is, sufficient and necessary conditions.
Findings
For any order difference incidence degree, the similarity incidence degree, the direct proportion incidence degree, the parallel incidence degree and the nearness incidence degree, it is proven that the perfect correlation relation is an equivalence relation. The set composed of all sequences Y that are equivalent to sequences X is studied, that is, the equivalence class of X. The structure and mutual relations of these equivalence classes are discussed, and the topological homeomorphism concept of incidence degree is introduced. The conclusion is obtained that the equivalence classes of the two incidence degrees must be the same when the topological homeomorphism is obtained.
Research limitations/implications
In this paper, only the perfect correlation relation of any order difference incidence degree, the similarity incidence degree, the direct proportion incidence degree, the parallel incidence degree and the nearness incidence degree are studied as equivalent relations.
Originality/value
Not only are the research results of several incidence degrees involved in this paper original but also many other effective incidence degrees have not done this basic research, so this paper opens up a research direction with theoretical significance.
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Marcin Nowak, Marta Pawłowska-Nowak, Małgorzata Kokocińska and Piotr Kułyk
With the use of the grey incidence analysis (GIA), indicators such as the absolute degree of grey incidence (εij), relative degree of grey incidence (rij) or synthetic degree of…
Abstract
Purpose
With the use of the grey incidence analysis (GIA), indicators such as the absolute degree of grey incidence (εij), relative degree of grey incidence (rij) or synthetic degree of grey incidence (ρij) are calculated. However, it seems that some assumptions made to calculate them are arguable, which may also have a material impact on the reliability of test results. In this paper, the authors analyse one of the indicators of the GIA, namely the relative degree of grey incidence. The aim of the article was to verify the hypothesis: in determining the relative degree of grey incidence, the method of standardisation of elements in a series significantly affects the test results.
Design/methodology/approach
To achieve the purpose of the article, the authors used the numerical simulation method and the logical analysis method (in order to draw conclusions from our tests).
Findings
It turned out that the applied method of standardising elements in series when calculating the relative degree of grey incidence significantly affects the test results. Moreover, the manner of standardisation used in the original method (which involves dividing all elements by the first element) is not the best. Much more reliable results are obtained by a standardisation that involves dividing all elements by their arithmetic mean.
Research limitations/implications
Limitations of the conducted evaluation involve in particular the limited scope of inference. This is since the obtained results referred to only one of the indicators classified into the GIA.
Originality/value
In this article, the authors have evaluated the model of GIA in which the relative degree of grey incidence is determined. As a result of the research, the authors have proposed a recommendation regarding a change in the method of standardising variables, which will contribute to obtaining more reliable results in relational tests using the grey system theory.
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This study aims to simultaneously and stochastically maximize autonomous flight performance of a variable wing incidence angle having an unmanned aerial vehicle (UAV) and its…
Abstract
Purpose
This study aims to simultaneously and stochastically maximize autonomous flight performance of a variable wing incidence angle having an unmanned aerial vehicle (UAV) and its flight control system (FCS) design.
Design/methodology/approach
A small UAV is produced in Iskenderun Technical University Drone Laboratory. Its wing incidence angle is able to change before UAV flight. FCS parameters and wing incidence angle are simultaneously and stochastically designed to maximize autonomous flight performance using an optimization method named simultaneous perturbation stochastic approximation. Obtained results are also benefitted during UAV flight simulations.
Findings
Applying simultaneous and stochastic design approach for a UAV having passively morphing wing incidence angle and its flight control system, autonomous flight performance is maximized.
Research limitations/implications
Permission of the Directorate General of Civil Aviation in Turkish Republic is necessary for real-time flights.
Practical implications
Simultaneous stochastic variable wing incidence angle having UAV and its flight control system design approach is so useful for maximizing UAV autonomous flight performance.
Social implications
Simultaneous stochastic variable wing incidence angle having UAV and its flight control system design methodology succeeds confidence, excellent autonomous performance index and practical service interests of UAV users.
Originality/value
Creating an innovative method to recover autonomous flight performance of a UAV and generating an innovative procedure carrying out simultaneous stochastic variable wing incidence angle having UAV and its flight control system design idea.
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Olusegun Emmanuel Akinwale, Owolabi Lateef Kuye and Olusoji James George
The brain drain challenge has become a cankerworm confronting not only the public health-care sector in Nigeria but almost all sectors of the national economy. This study aims to…
Abstract
Purpose
The brain drain challenge has become a cankerworm confronting not only the public health-care sector in Nigeria but almost all sectors of the national economy. This study aims to explore the push factors responsible for brain drain incidence among the migrated, JAPA, physicians to other global work environments. The study investigates the mediating role of capacity development among migrated, JAPA, physicians between the health-care infrastructural deficit and brain drain syndrome.
Design/methodology/approach
This study used a survey cross-sectional research design to examine the 214 migrated physicians in four notable perceived countries (UK, USA, Canada and Australia). The study used a probability sampling strategy to survey a self-administered online research instrument. The study adapted a battery of scales from several authors to measure the relevant constructs of this study. Hierarchical multiple regression was used to examine factors that provoke the incidence of brain drain burden among the JAPA Physicians. While Macro Hayes Process was used to investigate the mediating role of capacity development among migrated physicians.
Findings
The study revealed from the “JAPA” physicians that working conditions are turbulent and utterly poor which led to the incidence of brain drain. The study indicated that poor remuneration and benefits are the predominant reason for JAPA physicians to European countries and USA/UK. The findings of the study demonstrated that restricted opportunities and poor standard of living in the country were additional factors responsible for the brain drain of Nigerian physicians to other international countries. The outcome of the study also illustrated that inadequate infrastructure and facilities are the dominant variables that pushed physicians to foreign nations. It was revealed that there is a toxic mix of several issues that led to a brain drain albatross among the migrated physicians from Nigeria. The last part of the study indicated that physicians’ capacity development was a game changer that would discourage brain drain incidence and establish motivation for working in Nigeria's public health-care sector.
Originality/value
The study has given a direction for providing succinct solutions to the cankerworm of brain drain that has depleted the Nigerian public health-care industry. It has proffered a possible trajectory that will reverse the JAPA syndrome among the professional health-care workforce. This will not only benefit the public health-care personnel but also be significant for all the human capital across all the sectors of the national economy of Nigeria.
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Simplice Asongu and Nicholas M. Odhiambo
This study assesses the relevance of foreign aid to the incidence of capital flight and unemployment in 20 countries in sub-Saharan Africa.
Abstract
Purpose
This study assesses the relevance of foreign aid to the incidence of capital flight and unemployment in 20 countries in sub-Saharan Africa.
Design/methodology/approach
The study is for the period 1996–2018, and the empirical evidence is based on interactive quantile regressions in order to assess the nexuses throughout the conditional distribution of the unemployment outcome variable.
Findings
From the findings, capital flight has a positive unconditional incidence on unemployment, while foreign aid dampens the underlying positive unconditional nexus. Moreover, in order for the positive incidence of capital flight to be completely dampened, foreign aid thresholds of 2.230 and 3.964 (% of GDP) are needed at the 10th and 25th quantiles, respectively, of the conditional distribution of unemployment. It follows that the relevance of foreign aid in crowding out the unfavourable incidence of capital flight on unemployment is significantly apparent only in the lowest quantiles or countries with below-median levels of unemployment. The policy implications are discussed.
Originality/value
The study complements the extant literature by assessing the importance of development assistance in how capital flight affects unemployment in sub-Saharan Africa.
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Kirti Boora, Sunita Deswal and Kapil Kumar Kalkal
The purpose of the current manuscript is to investigate the reflection of plane waves in a rotating, two-dimensional homogeneous, initially stressed, nonlocal orthotropic…
Abstract
Purpose
The purpose of the current manuscript is to investigate the reflection of plane waves in a rotating, two-dimensional homogeneous, initially stressed, nonlocal orthotropic thermoelastic solid half-space based on dual-phase-lag model.
Design/methodology/approach
The reflection phenomenon has been utilized to study the effects of initial stress, rotation and nonlocal parameter on the amplitude ratios. During the reflection phenomenon three coupled waves, namely quasi displacement primary wave (qP), quasi thermal wave (qT) and quasi displacement secondary wave (qSV) have been observed in the medium, propagating with distinct velocities. After imposing the suitable boundary conditions, amplitude and energy ratios of the reflected waves are obtained in explicit form.
Findings
With the support of MATLAB programming, the amplitude ratios and energy ratios are plotted graphically to display the effects of rotation, initial stress and nonlocal parameters. Moreover, the impact of anisotropy and phase lags is also observed on the reflection coefficients of the propagating waves.
Originality/value
In the current work, we have considered rotation and nonlocality parameters in an initially stressed orthotropic thermoelastic half-space, which is lacking in the published literature in this field. The introduction of these parameters in a nonlocal orthotropic thermoelastic medium provides a more realistic model for these studies. The present work is valuable for the analysis of orthotropic thermoelastic problems involving rotation, initial stress and nonlocality parameters.
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Francesco Andreoli, Vincenzo Prete and Claudio Zoli
This paper investigates one of the potential costs of rising segregation in American cities by evaluating empirically the extent at which ethnic-based segregation contributes to…
Abstract
Purpose
This paper investigates one of the potential costs of rising segregation in American cities by evaluating empirically the extent at which ethnic-based segregation contributes to the onset and the speed of propagation of the COVID-19 pandemic.
Design/methodology/approach
Regression analysis based on matched data on early incidence of COVID-19 cases, segregation and covariates. Identification resorts on variations in segregation across MSAs and heterogeneity in the geography and timing of stay-at-home orders.
Findings
One cross-MSA standard deviation increase in segregation leads to a significant and robust rise of COVID-19 cases of 8.7 per 100,000 residents across urban counties.
Originality/value
Combines spatial data on COVID-19 cases and segregation; use of a new segregation measure; focus on early incidence of the pandemic and its drivers.
Details
Keywords
Austin Zygmunt, Kahiye Warsame, Richard G. Mather, Lori McKinnon, Anne Philipneri, Stone Li and Sandya Menon
The physical environment of correctional facilities promote infectious disease transmission and outbreaks. The purpose of this study is to compare the COVID-19 burden between the…
Abstract
Purpose
The physical environment of correctional facilities promote infectious disease transmission and outbreaks. The purpose of this study is to compare the COVID-19 burden between the correctional facility (incarcerated individuals and staff members) and non-correctional facility population in Ontario during the COVID-19 pandemic.
Design/methodology/approach
All individuals in Ontario with a laboratory confirmation of SARS-CoV-2 between 15 January 2020 and 31 December 2022 and entered into the provincial COVID-19 data were included. Cases were classified as a correctional facility case (living or working in a correctional facility) or a non-correctional facility case. COVID-19 vaccination status was obtained from the provincial COVID-19 vaccine registry. Statistics Canada census data were used to calculate COVID-19 incidence and hospitalization rates for incarcerated cases and the non-correctional facility population.
Findings
Between 15 January 2020 and 31 December 2022, there were 1,550,045 COVID-19 cases in Ontario of which 8,292 (0.53%) cases were reported in correctional (63.8% amongst incarcerated individuals, 18.6% amongst staff and 17.7% amongst an unknown classification) and 1,541,753 (99.47%) were non-correctional facility cases. Most cases in correctional facilities were men (83.8%) and aged 20–59 years (93.1%). COVID-19 incidence and hospitalization rates were generally higher among incarcerated individuals compared to the non-correctional facility population throughout the study period. COVID-19 incidence peaked in January 2022 for both the correctional facility population (21,543.8 per 100,000 population) and the non-correctional facility population (1915.1 per 100,000 population). The rate of COVID-19 hospitalizations peaked for the correctional facility population aged 20–59 in March 2021 (70.7 per 100,000 population) and in April 2021 for the non-correctional facility population aged 20–59 (19.8 per 100,000 population). A greater percentage of incarcerated individuals (73.0%) were unvaccinated at time of their COVID-19 diagnosis compared to the non-correctional facility population (49.3%). Deaths amongst correctional facility cases were rare (0.1%, 6 / 8,292) compared to 1.0% of non-correctional facility cases (n = 15,787 / 1,541,753).
Originality/value
During the COVID-19 pandemic, individuals incarcerated in correctional facilities in Ontario had higher COVID-19 incidence and hospitalization rates compared to the non-correctional facility population. These results support prioritizing incarcerated individuals for public health interventions to mitigate COVID-19 impacts in correctional facilities.
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Miranda Nonikashvili, Maia Kereselidze, Otar Toidze and Tina Beruchashvili
This study aims to examine the availability and comprehensiveness of policies pertaining to colorectal cancer (CRC) in Central, Eastern European and South Caucasus countries, as…
Abstract
Purpose
This study aims to examine the availability and comprehensiveness of policies pertaining to colorectal cancer (CRC) in Central, Eastern European and South Caucasus countries, as it is a major public health concern in these regions and the second most common cause of cancer deaths among women.
Design/methodology/approach
We performed a scoping review using the Arksey and O'Malley methodology, searching for publicly available policy documents from 18 countries. We described the prevention methods and activities in each country based on the World Health Organization guidelines for CRC screening.
Findings
Our research found that most countries had at least five policies related to CRC prevention, which most commonly included primary, secondary and tertiary prevention measures. Elements such as promoting healthy lifestyle choices and implementing screening methods such as fecal occult blood tests, fecal immunochemical tests or colonoscopy were frequently mentioned in these policies. However, target age ranges varied among countries. Our analysis revealed a pressing need to increase the availability and utilization of CRC screening in these countries.
Research limitations/implications
One of the main limitations of this study is that it is a desk review conducted using internet-based resources, which may have missed important sources or recent policy documents that are not yet available online. Despite our efforts to include all relevant policies, it is possible that we overlooked other policies that contain relevant information, such as those that cover cancer treatment methods. Additionally, our search excluded primary healthcare and universal healthcare coverage policies, which could include important information on CRC prevention and control activities. Additionally, as a scoping review approach was used, no critical assessment of the included studies or literature was conducted. Furthermore, due to the limited number of countries included, the comparability of the findings is limited. In future research, it would be beneficial to expand the study and collect new data from decision-makers and stakeholders to further investigate these hypotheses. It is also important to note that the presence of a policy document is not the end goal, as it is simply a step toward better outcomes.
Practical implications
In summary, our research highlights the need for improved and unified efforts toward preventing and detecting CRC in Central, Eastern European and South Caucasus countries. This knowledge can be used to focus efforts on developing a standardized policy document and national screening program that can be adapted to meet the unique needs of each country. The importance of CRC screening, regardless of need, must be emphasized in order to aid in the transition from curative to preventive cancer care. Our study highlights the need for more detailed and science-based policies for CRC prevention and screening in Central, Eastern European and South Caucasus countries. While many countries have policies in place, they often lack key components and do not fully reflect current evidence-based guidelines. To improve population health outcomes, further research is needed to understand the implementation and enforcement of these policies as well as their impact on cancer incidence and survival. As the screening landscape evolves, countries may learn from each other and a better understanding of the complex policy frameworks that impact CRC screening is needed so that countries can update and tailor policy documents to their specific situations.
Social implications
In conclusion, policymakers in Central, Eastern European and South Caucasus countries have implemented various policy approaches to prevent and control the CRC. The effectiveness of these approaches varies across countries and depends on several factors, including the availability of resources, the level of public awareness and the political will to implement effective policies. Further research is needed to determine the most effective policy approaches for CRC prevention in these regions and to ensure that the right policies are in place to reduce the incidence and impact of this disease.
Originality/value
The study aimed to identify gaps in existing research and areas for future work by mapping, categorizing and organizing existing evidence on CRC policies in Central, Eastern European and South Caucasus countries. Additional research is necessary to understand the implementation and enforcement of these policies and how they impact health outcomes such as cancer incidence and survival.
Highlights
CRC policy is heterogeneous in Central and Eastern Europe and the South Caucasus region.
There are particularly important differences regarding the implementation of CRC screening.
Cancer screening and palliative care approaches were less frequently included.
Variations exist in the comprehensiveness of policy by prevention level and country.
CRC policy is heterogeneous in Central and Eastern Europe and the South Caucasus region.
There are particularly important differences regarding the implementation of CRC screening.
Cancer screening and palliative care approaches were less frequently included.
Variations exist in the comprehensiveness of policy by prevention level and country.
Details