Performance evaluation of bearing degradation based on stationary wavelet decomposition and extra trees regression

2018 ◽  
Vol 15 (5) ◽  
pp. 646-658 ◽  
Author(s):  
Vinod Nistane ◽  
Suraj Harsha
Keyword(s):  
Wavelet Decomposition ◽  
Early Stage ◽  
Content Type ◽  
Dissimilarity Data ◽  
Evaluation Of Performance ◽  
Failure State ◽  
Bearing Failures ◽  
Degradation Monitoring ◽  
Dominance Level ◽  
Degradation Indicator

Purpose In rotary machines, the bearing failure is one of the major causes of the breakdown of machinery. The bearing degradation monitoring is a great anxiety for the prevention of bearing failures. This paper aims to present a combination of the stationary wavelet decomposition and extra-trees regression (ETR) for the evaluation of bearing degradation. Design/methodology/approach The higher order cumulants features are extracted from the bearing vibration signals by using the stationary wavelet decomposition (stationary wavelet transform [SWT]). The extracted features are then subjected to the ETR for obtaining normal and failure state. A dominance level curve build using the dissimilarity data of test object and retained as health degradation indicator for the evaluation of bearing health. Findings Experiment conducts to verify and assess the effectiveness of ETR for the evaluation of performance of bearing degradation. To justify the preeminence of recommended approach, it is compared with the performance of random forest regression and multi-layer perceptron regression. Originality/value The experimental results indicated that the presently adopted method shows better performance for detecting the degradation more accurately at early stage. Furthermore, the diagnostics and prognostics have been getting much attention in the field of vibration, and it plays a significant role to avoid accidents.

Quality of life in breast cancer sufferers

2016 ◽  
Vol 29 (7) ◽  
pp. 721-732 ◽  
Author(s):  
Ahmed Essmat Shouman ◽  
Nahla Fawzy Abou El Ezz ◽  
Nivine Gado ◽  
Amal Mahmoud Ibrahim Goda
Keyword(s):  
Breast Cancer ◽  
Quality Of Life ◽  
Family Income ◽  
Early Stage ◽  
Functional Domain ◽  
Related Factors ◽  
Specific Patient ◽  
Content Type ◽  
Factors Affecting

Purpose – The purpose of this paper is to measure health-related quality of life (QOL) among patients with early stage cancer breast under curative treatment at department of oncology and nuclear medicine at Ain Shams University Hospitals. Identify factors affecting QOL among these patients. Design/methodology/approach – A cross-sectional study measured QOL among early stage female breast cancer (BC) patients and determined the main factors affecting their QOL. Three interviewer administered questionnaires were used. Findings – The physical domain mostly affected in BC patients and the functional domain least. Socio-demographic factors that significantly affected BC patients QOL scores were patient age, education, having children and family income. Specific patient characteristics include caregiver presence – a factor that affected different QOL scores. Age at diagnosis, affection in the side of the predominant hand, post-operative chemotherapy and difficulty in obtaining the medication were the disease-related factors that affected QOL scores. Originality/value – The final model predicting QOL for early stage female BC patients included age, education and difficulty in obtaining the medication as determinants for total QOL score. Carer presence was the specific patient characteristic that affected different QOL scores.

Antecedents of growth-oriented entrepreneurship before and during the Greek economic crisis

2017 ◽  
Vol 24 (3) ◽  
pp. 528-544 ◽  
Author(s):  
Ioannis Giotopoulos ◽  
Alexandra Kontolaimou ◽  
Aggelos Tsakanikas
Keyword(s):  
Work Experience ◽  
Early Stage ◽  
New Ventures ◽  
High Growth ◽  
Content Type ◽  
Crisis Period ◽  
Individual Level ◽  
Level Data ◽  
The Social ◽  
Before And After

Purpose The purpose of this paper is to explore potential drivers of high-growth intentions of early-stage entrepreneurs in Greece before and after the onset of the financial crisis of 2008. Design/methodology/approach To this end, the authors use individual-level data retrieved from Global Entrepreneurship Monitor annual surveys (2003-2015). Findings The results show that high-growth intentions of Greek entrepreneurs are driven by different factors in the crisis compared to the non-crisis period. Male entrepreneurs and entrepreneurs with significant work experience seem to be more likely to be engaged in growth-oriented new ventures during the crisis period. The same appears to hold for entrepreneurs who are motivated by an opportunity and also perceive future business opportunities in adverse economic conditions. On the other hand, the educational level and the social contacts of founders with other entrepreneurs are found to drive ambitious Greek entrepreneurship in the years before the crisis, while they were insignificant after the crisis outbreak. Originality/value Based on the concept of ambitious entrepreneurship, this study contributes to the literature by investigating the determinants of entrepreneurial high-growth expectations in the Greek context emphasizing the crisis period in comparison to the pre-crisis years.

Challenges faced by youth social entrepreneurs in Malaysia: career transition to become a social entrepreneur

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Nur Raihan Che Nawi ◽  
Mohd Mursyid Arshad ◽  
Steven Eric Krauss ◽  
Ismi Arif Ismail
Keyword(s):  
Social Entrepreneurship ◽  
Early Stage ◽  
Career Transition ◽  
Social Enterprises ◽  
Social Entrepreneur ◽  
Social Entrepreneurs ◽  
Content Type ◽  
Data Saturation ◽  
Analyse Data ◽  
Voice Recorder

Purpose The practice of social entrepreneurship has grown rapidly around the world, including in Malaysia where it is still considered to be at an early stage. Nevertheless, little is known about the career transition among youth who choose careers as social entrepreneurs. The purpose of this study is to explore the challenges faced by youth social entrepreneurs who run social enterprises in Malaysia. Design/methodology/approach This study used a qualitative approach to collect and analyse data to answer the research questions. Seven youth social entrepreneurs were interviewed until data saturation was met. An interview guide was created for the purposes of conducting the interviews. The interviews were recorded using a voice recorder. Data were transcribed verbatim and grouped in order to identify the codings, categories and themes. Findings The findings show the career transition to become a social entrepreneur, as well as the major challenges that youth social entrepreneurs face, which include acclimatising to the life and career of a social entrepreneur and not getting support from family. Practical implications The study findings are also significant for presenting valuable data on the experience of the developing social entrepreneur. The qualitative nature of the study provides valuable experiential insight into the lives and struggles of young social entrepreneurs in Malaysia. The findings will allow local authorities and social entrepreneurship regulatory agencies to design initiatives and plan actions intended to overcome the challenges. Originality/value This study makes an original contribution by showing that the process of career development as a social entrepreneur has given meaning to the informants. Despite presenting many challenges, social entrepreneurship has reinforced the role of youth social entrepreneurs, especially in relation to social responsibility.

Geochemical evaluation of the in-situ regolith of Madengi hills of Dodoma, Tanzania. Implication on bedrock mapping and delineating gold mineralization target

2021 ◽  
pp. geochem2021-074
Author(s):  
Godson Godfray
Keyword(s):  
Gold Mineralization ◽  
Early Stage ◽  
Shear Zones ◽  
Soil Geochemistry ◽  
Residual Soils ◽  
Content Type ◽  
Geochemical Evaluation ◽  
Supplementary Material ◽  
Pathfinder Elements

Successful gold exploration projects depend on a piece of clear information on the association between gold, trace elements, and mineralization controlling factors. The use of soil geochemistry has been an important tool in pinpointing exploration targets during the early stage of exploration. This study aimed to establish the gold distribution, the elemental association between gold and its pathfinder elements such as Cu, Zn, Ag, Ni, Co, Mn, Fe, Cd, V, Cr, Ti, Sc, In, and Se and identify lithologies contributing to the overlying residual soils. From cluster analysis, a high similarity level of 53.93% has been shown with Ag, Cd, and Se at a distance level of 0.92. Au and Se have a similarity level of 65.87% and a distance level of 0.68, hence is proposed to be the most promising pathfinder element. PCA, FA, and the Pearson's correlation matrix of transformed data of V, Cu, Ni, Fe, Mn, Cr, and Co and a stronger correlation between Pb and U, Th, Na, K, Sn, Y, Ta and Be shows that source gold mineralization might be associated with both hornblende gneisses interlayered with quartzite, tonalite, and tonalitic orthogneiss. From the contour map and gridded map of Au and its pathfinder elements, it has been noted that their anomalies and target generated are localized in the Northern part of the area. The targets trend ESE to WNW nearly parallel to the shear zones as a controlling factor of Au mineralization emplacement.Supplementary material:https://doi.org/10.6084/m9.figshare.c.5721965

Benefits and challenges to applying IPD: experiences from a Norwegian mega-project

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Monique Rieger Rodrigues ◽  
Søren Munch Lindhard
Keyword(s):  
Early Stage ◽  
Lessons Learned ◽  
Structured Interviews ◽  
Main Concept ◽  
Content Type ◽  
Positive Effects ◽  
Collaboration And Communication ◽  
Traditional Construction ◽  
Supporting Element ◽  
Early Phases

Purpose The traditional construction delivery method is challenged by low trust and collaboration issues, resulting in increased project costs. The integrated project delivery (IPD) method is developed, through a contractual agreement, to overcome these challenges by creating a common set of terms, expectations and project goals. Design/methodology/approach A singular construction case was followed during a four-month period. Data collection consisted of contract documents and a series of semi-structured interviews with representatives from the owner, design-group and contractors. Findings The IPD contract was found to have a number of positive effects; it improved project behavior (e.g. trust, collaboration and communication), increased ownership among project participants and improved buildability of the design, leading to fewer surprises and interruptions in the construction phase. The study also revealed a number of challenges including contractual and legal challenges and involving too many participants in the early phases. Moreover, co-location was identified as a particular important supporting element, to build relations and improve collaboration. Originality/value This research identified lessons learned from the application, as well as initial barriers and persistent barriers for implementing IPD. To improve IPD application the top three lessons were as follows: 1) the contractual documents should be adapted and signed at an early stage as this increases financial transparency, 2) cost estimates should be carried as an iterative process and project main concept be freezed at an early stage to increase understanding and minimize risks, 3) only the most important project developers should be involved in the early phases, to avoid going into detailed design issues before the main concept is completed.

Stock markets' reaction to COVID-19: evidence from the six WHO regions

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Anas Ali Al-Qudah ◽  
Asma Houcine
Keyword(s):  
Stock Returns ◽  
Stock Markets ◽  
Early Stage ◽  
Eastern Mediterranean ◽  
Abnormal Returns ◽  
Western Pacific ◽  
Content Type ◽  
Panel Data Regression ◽  
Daily Stock Returns ◽  
The Impact

PurposeThis study investigates the effects of the COVID-19 outbreak on daily stock returns for the six major affected WHO Regions, namely: Africa, Americas, Eastern Mediterranean, Europe, South-East Asia and Western Pacific.Design/methodology/approachThis study uses an event study method and panel-data regression models to examine the effect of the daily increase in the number of COVID-19 confirmed cases on daily stock returns from 1 March to 1 August 2020 for the leading stock market in major affected countries in the WHO regions.FindingsThe results reveal an adverse impact of the daily increasing number of COVID-19 cases on stock returns and stock markets fell quickly in response to the pandemic. The findings also suggest that negative market reaction was strong during the early stage of the outbreak between the 26th and 35th days after the initial confirmed cases. We further find that stock markets in the Western Pacific region experienced more negative abnormal returns as compared to other regions. The results also confirm that feelings of fear among investors turned out to be a mediator and a transmission channel for the effect of COVID-19 outbreak on the stock markets.Research limitations/implicationsThis study contributes to financial literature in two ways. First, we contribute to existing literature that has examined the effect of various catastrophes and crises on the stock markets Second, we contribute to the recent emerging literature that examines the impact of COVID-19 on financial markets.Practical implicationsThe study may have implications for policymakers to deal with this outbreak without triggering uncertainty in stock markets and reassure investors' confidence. The study may also be of interest to investors, managers, financial analysts by revealing how the stock markets quickly respond to outbreaks.Originality/valueThis study is the first study to examine the impact of the COVID-19 outbreak on the leading stock markets of the WHO regions.

Kit preparation for mixed-model assembly: efficiency impact of confirmation methods

2019 ◽  
Vol 119 (3) ◽  
pp. 547-560 ◽  
Author(s):  
Patrik Fager
Keyword(s):  
Learning Curve ◽  
Design Methodology ◽  
Mixed Model ◽  
Early Stage ◽  
Time Efficiency ◽  
Content Type ◽  
Order Batching ◽  
The Impact ◽  
Mixed Model Assembly ◽  
Practical Implications

PurposeConfirmations are applied in kit preparation for mixed-model assembly to promote quality, but research that explains the impact on time efficiency has been lacking. The purpose of this paper is to determine the extent to which the type of confirmation method relates to time-efficient kit preparation when order batching is applied.Design/methodology/approachAn industrially relevant laboratory experiment is applied, simulating kit preparation with order batching for mixed-model assembly. The time efficiency is studied as associated with four confirmation methods – barcode ring scanner, button presses, voice commands and RFID-reading wristbands – when applied as pick-from and place-to confirmation. Furthermore, the paper also considers the quality outcome.FindingsEfficiency is promoted by methods that minimise interrupting the picker’s motions when performing pick-from confirmations and with methods that allow each hand to place components and perform place-to confirmations simultaneously – here represented by button presses and RFID-reading wristbands. Moreover, combining various methods for the tasks of pick-from or place-to confirmation can benefit efficiency.Research limitations/implicationsPickers at an early stage of the learning curve (one shift of training) were considered.Practical implicationsThe findings promote the customised applications of picking information systems in industry.Social implicationsCombining various methods for the tasks of pick-from and place-to confirmation can provide more fitting applications that better align with the picker’s preferences.Originality/valueCombinations of various methods when applied as either pick-from or place-to confirmation, or both, are studied.

Identifying high potentials early: case study

2018 ◽  
Vol 37 (9/10) ◽  
pp. 684-696 ◽  
Author(s):  
Igor Kotlyar
Keyword(s):  
Leadership Development ◽  
University Students ◽  
Early Stage ◽  
Development Program ◽  
Content Type ◽  
Leadership Potential ◽  
High Potentials ◽  
Early Case ◽  
Leadership Development Program

Purpose Driven by a shortage of leadership capacity, companies are seeking to identify leadership talent earlier. Some companies are introducing programs to identify leadership potential among university students and then hire “high potentials” directly into management designate roles. The purpose of this paper is to explore one such early-stage leadership development program. Currently, little information is available about these initiatives. Design/methodology/approach Case study based on interviews with 18 managers and director of HR and archival employee records. Findings This case study provides a detailed description of an early-stage leadership identification and development program. This program has been developed to identify leadership talent among senior university students prior to hiring and onboarding, provide support, training and development and fast-track them into leadership positions. The study provides insight into the challenges and effectiveness of an early-stage leadership program and offers some practical implications. Originality/value To the author’s knowledge, this is the first study to document a leadership development program that identifies “high potentials” among university students for the purpose of developing them into company leaders.

Hitting the right note for child and adolescent mental and emotional wellbeing: a formative qualitative evaluation of Sistema Scotland’s “Big Noise” orchestral programme

2016 ◽  
Vol 15 (1) ◽  
pp. 25-36 ◽  
Author(s):  
Christopher Harkins ◽  
Lisa Garnham ◽  
Aileen Campbell ◽  
Carol Tannahill
Keyword(s):  
Mental Health ◽  
Mental Health Problems ◽  
Early Stage ◽  
Qualitative Evaluation ◽  
Qualitative Assessment ◽  
Potential Contribution ◽  
Emotional Wellbeing ◽  
Structured Interviews ◽  
Content Type ◽  
Causal Pathways

Purpose – Previous research emphasises the need for preventative interventions to reduce mental health problems among disadvantaged children and adolescents. There is however little consensus concerning the delivery and impacts of such interventions particularly non-clinical, arts-based models delivered within community settings. The purpose of this paper is to begin to address this deficit through a qualitative assessment of the short- to medium-term impacts to participants’ mental and emotional wellbeing within Sistema Scotland’s Big Noise orchestral programme. Design/methodology/approach – Semi-structured interviews, observation, participant drawing exercise, participatory filmmaking, focus group and analysis of programme engagement were undertaken to examine the mental and emotional wellbeing impacts of the programme which are observable at this early stage of programme delivery and participants’ lives. Findings – The qualitative findings indicate that participation in the Big Noise programme enhances participant mental and emotional wellbeing in three ways; first, the happiness and enjoyment of taking part in the programme and orchestra, particularly from music making; second, the security, belonging and relationships fostered through participation; the quality of musician/participant relationship is important here as is programme design which enables support, routine and structure; and third, increased pride, confidence and self-esteem, as a result of acquiring difficult musical skills, receiving regular praise and having frequent opportunities to demonstrate these acquired skills through regular orchestral performances. Originality/value – There is little evidence or understanding of community-based, preventative, arts interventions like Big Noise: their delivery, their life-course impacts and their potential contribution to mental health and to addressing social and health inequalities. The causal pathways in the field are under-theorised. These early findings are important as they serve as an important basis from which to consider the programme’s wider and longer term impacts, which will be assessed through an on-going longitudinal, mixed method summative evaluation.

scholarly journals Foxp3+ T Regulatory Cells as a Potential Target for Immunotherapy against Primary Infection with Echinococcus multilocularis Eggs

2018 ◽  
Vol 86 (10) ◽  
Author(s):  
Junhua Wang ◽  
Rita Cardoso ◽  
Nelson Marreros ◽  
Norbert Müller ◽  
Britta Lundström-Stadelmann ◽  
...  
Keyword(s):  
Transforming Growth Factor Beta ◽  
Echinococcus Multilocularis ◽  
Transforming Growth Factor ◽  
Early Stage ◽  
Expression Profiles ◽  
Growth Potential ◽  
Interleukin 4 ◽  
Content Type ◽  
Hepatic Expression ◽  
Th2 Immune Response

ABSTRACT Alveolar echinococcosis (AE) is a lethal disease caused by infection with the metacestode stage of the helminth Echinococcus multilocularis, which develops into a tumorlike mass in susceptible intermediate hosts. The growth potential of this parasite stage is directly linked to the nature of the surrounding periparasitic immune-mediated processes. In a first step (experiment 1), mice were orally infected with E. multilocularis eggs, to be used for assessing the hepatic expression profiles of 15 selected cytokine and chemokine genes related to acquired immunity from 21 to 120 days postinfection. The early stage of infection in immunocompetent animals was marked by a mixed Th1/Th2 immune response, as characterized by the concomitant presence of gamma interferon (IFN-γ) and interleukin-4 (IL-4) and their related chemokines. At the late stage of AE, the profile extended to a combined tolerogenic mode including Foxp3, IL-10, and transforming growth factor beta (TGF-β) as key components. In a second step (experiment 2), the effect of T regulatory cell (Treg) deficiency on metacestode growth was assessed in E. multilocularis-infected DEREG (depletion of regulatory T cells) mice upon induction of Treg deficiency with diphtheria toxin (DT). The parasite lesions were significantly smaller in the livers of treated mice than in corresponding control groups. Foxp3+ Tregs appear to be one of the key players in immune-regulatory processes favoring metacestode survival by affecting antigen presentation and suppressing Th1-type immune responses. For these reasons, we suggest that affecting Foxp3+ Tregs could offer an attractive target in the development of an immunotherapy against AE.

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