By evaluating the generalist indexes of 2,683 CEOs from 1,954 listed firms in the Chinese A-share market from 2015 to 2019, this study used regressions and two-stage least squares regression to investigate how competitive generalist CEOs are in China. Generalist CEOs are more competitive than specialist CEOs in the majority of sectors, particularly in the construction, retail, and wholesale sectors. This study also showed that generalists receive more compensation. Moreover, senior generalist CEOs are more competitive than young CEOs, and male managers receive more compensation than females. Meanwhile, this research uncovered a significant relationship between generalist CEOs and their income in state-owned enterprises (SOEs) but not in non-SOEs. These findings help us to understand CEO compensation spillovers in the Chinese employment market.
{"title":"How Competitive are Generalist CEOs in an Emerging Economy?","authors":"Hai LONG, Jin WANG","doi":"10.59879/hkkfn","DOIUrl":"https://doi.org/10.59879/hkkfn","url":null,"abstract":"By evaluating the generalist indexes of 2,683 CEOs from 1,954 listed firms in the Chinese A-share market from 2015 to 2019, this study used regressions and two-stage least squares regression to investigate how competitive generalist CEOs are in China. Generalist CEOs are more competitive than specialist CEOs in the majority of sectors, particularly in the construction, retail, and wholesale sectors. This study also showed that generalists receive more compensation. Moreover, senior generalist CEOs are more competitive than young CEOs, and male managers receive more compensation than females. Meanwhile, this research uncovered a significant relationship between generalist CEOs and their income in state-owned enterprises (SOEs) but not in non-SOEs. These findings help us to understand CEO compensation spillovers in the Chinese employment market.","PeriodicalId":49454,"journal":{"name":"Sylwan","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135107225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study investigates the causal effect of the earthquake in Turkey on construction, transportation, and insurance stocks. The results reveal a significant negative impact on these stocks. This indicates that the earthquake induced a high level of uncertainty, resulting in a substantial negative influence on the stock market's value on a subsequent day. In addition, the results indicate that stocks are lower than expected without an earthquake. The point-wise causal effect refers to the variation between the expected and actual data, and it remains relatively stable near zero until the action is implemented, at which point it quickly decreases and then increases. In relative terms, the construction stock is more affected by the earthquake, followed by the transportation stock. The findings have important implications for investors and policymakers, highlighting the importance of preparing for natural disasters to reduce their negative impact on the stock market.
{"title":"Do earthquakes shake stock prices? Evidence from Turkey","authors":"Haibo JIA, Khalid Khan","doi":"10.59879/kaqfb","DOIUrl":"https://doi.org/10.59879/kaqfb","url":null,"abstract":"This study investigates the causal effect of the earthquake in Turkey on construction, transportation, and insurance stocks. The results reveal a significant negative impact on these stocks. This indicates that the earthquake induced a high level of uncertainty, resulting in a substantial negative influence on the stock market's value on a subsequent day. In addition, the results indicate that stocks are lower than expected without an earthquake. The point-wise causal effect refers to the variation between the expected and actual data, and it remains relatively stable near zero until the action is implemented, at which point it quickly decreases and then increases. In relative terms, the construction stock is more affected by the earthquake, followed by the transportation stock. The findings have important implications for investors and policymakers, highlighting the importance of preparing for natural disasters to reduce their negative impact on the stock market.","PeriodicalId":49454,"journal":{"name":"Sylwan","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135609410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
One of the earliest symptoms in patients affected by SARS-CoV-2 virus is decreased blood oxygen levels. This silent hypoxemia or happy hypoxia is one of several mysteries of the ongoing COVID-19 pandemic. It is amazing that patients with coronavirus disease (COVID-19) present oxygen blood levels incompatible with life and even without dyspnea which is defying basic biology. The explanation for silent hypoxemia is complex and is usually avoided in medical journals. The purpose of this work is to draw attention to the importance of dissolved oxygen levels in drinking water supplied to the population and their relationship to the current COVID-19 pandemic. This report was prepared in accordance with SQUIRE 2.0 guidelines
{"title":"The Unexpected capacity of Human Body to dissociate the water molecule, like chlorophyll in plants, and dissolved oxygen levels in drinking water. Implications in the study and treatment of COVID 19 patients.","authors":"Arturo Solís Herrera","doi":"10.59879/xqgg6","DOIUrl":"https://doi.org/10.59879/xqgg6","url":null,"abstract":"One of the earliest symptoms in patients affected by SARS-CoV-2 virus is decreased blood oxygen levels. This silent hypoxemia or happy hypoxia is one of several mysteries of the ongoing COVID-19 pandemic. It is amazing that patients with coronavirus disease (COVID-19) present oxygen blood levels incompatible with life and even without dyspnea which is defying basic biology. The explanation for silent hypoxemia is complex and is usually avoided in medical journals. The purpose of this work is to draw attention to the importance of dissolved oxygen levels in drinking water supplied to the population and their relationship to the current COVID-19 pandemic. This report was prepared in accordance with SQUIRE 2.0 guidelines","PeriodicalId":49454,"journal":{"name":"Sylwan","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135799914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In the new wave of technological revolution, information technology is currently the most innovative areas around the world. Technological innovation is increasingly focused on digitalization. However, little research has attempted to investigate method to measure the digitalization of technological innovation and its impact. Based on longitudinal multiple data sources, including comprising patent documents, annual reports of listed Chinese manufacturing firms, a third-party database. We introduce a novel construct, namely digital technology proximity, to capture how firms digitize their technological innovation based on social network. Meanwhile, we consider firms’ digital transformation performance, measured by the proportion of digital-related revenue, as the impact of digitalization of technological innovation. Our unbalanced-panel regression and robustness tests reveal a positive link between digitalization of technological innovation and firms’ digital transformation performance, supporting the notion that technological innovation digitalization empowers firms’ digital transformation. In addition, digital innovation ability exerts a significant mediating effect for digitalization of technological innovation. This research introduces a new method of measuring the digitalization of technological innovation and its impact on digital transformation.
{"title":"From non-digital to digital: Digitalization of technological innovation and firms’ digital transformation performance","authors":"Cheng Zhou, Qian Chang","doi":"10.59879/blwxm","DOIUrl":"https://doi.org/10.59879/blwxm","url":null,"abstract":"In the new wave of technological revolution, information technology is currently the most innovative areas around the world. Technological innovation is increasingly focused on digitalization. However, little research has attempted to investigate method to measure the digitalization of technological innovation and its impact. Based on longitudinal multiple data sources, including comprising patent documents, annual reports of listed Chinese manufacturing firms, a third-party database. We introduce a novel construct, namely digital technology proximity, to capture how firms digitize their technological innovation based on social network. Meanwhile, we consider firms’ digital transformation performance, measured by the proportion of digital-related revenue, as the impact of digitalization of technological innovation. Our unbalanced-panel regression and robustness tests reveal a positive link between digitalization of technological innovation and firms’ digital transformation performance, supporting the notion that technological innovation digitalization empowers firms’ digital transformation. In addition, digital innovation ability exerts a significant mediating effect for digitalization of technological innovation. This research introduces a new method of measuring the digitalization of technological innovation and its impact on digital transformation.","PeriodicalId":49454,"journal":{"name":"Sylwan","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136008831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Juana Garcia Hernandez, Ana Rosa Rodriguez Luna, Eduardo Salvador Lopez Hernandez, Antonio Fernandez Crispin, Maria de los Angeles Chamorro Zarate
Climate change (CC) implies recent, rapid and more intense changes in climate. Its effects are reflected by the planet's natural processes and in human activities that impact socioeconomic and environmental systems. The research objective was to identify the perception of CC of the inhabitants of Cúlico 2nd Section, Huimango 1st Section and ejido La Chonita, through the Correspondence Analysis (CA) and vulnerability elements, estimating the criteria of Exposure (E), Sensitivity (S) and Adaptive Capacity (CA) that allows strengthening, through social participation, the capacities and values of the population. The study area is located near oil fields that generate environmental impacts, mainly on cocoa (Theobroma cacao) and corn (Zea mays) crops. A qualitative and quantitative analysis was carried out on a sample of 180 individuals. The results suggest that the population is exposed to the consequences of climatic events and degradation of natural resources, that there is sensitivity in their productive systems to diseases and in the quality of basic services, which limits the capacity for adequate response; it is important to generate actions to address local vulnerability, to strengthen the capacities and socio-environmental values of the population and to implement mitigation and adaptation actions, based on social participation and the formation of collaborative networks with other communities
气候变化(CC)指最近的、迅速的和更剧烈的气候变化。它的影响反映在地球的自然过程和影响社会经济和环境系统的人类活动中。研究目的是通过对应分析(CA)和脆弱性因素，估计暴露(E)、敏感性(S)和适应能力(CA)的标准，通过社会参与，加强人口的能力和价值观，确定Cúlico第二区、惠曼戈第一区和ejido La Chonita居民对CC的看法。研究区域位于对环境产生影响的油田附近，主要是对可可(Theobroma cacao)和玉米(Zea mays)作物产生影响。对180人的样本进行了定性和定量分析。结果表明，人口受到气候事件和自然资源退化的后果的影响，其生产系统对疾病和基本服务的质量很敏感，这限制了作出适当反应的能力;必须在社会参与和与其他社区形成协作网络的基础上，采取行动解决当地的脆弱性问题，加强人口的能力和社会环境价值，并实施缓解和适应行动
{"title":"Perception of vulnerability to climate change in rural communities of cunduac�n, Tabasco: adaptation strategy","authors":"Juana Garcia Hernandez, Ana Rosa Rodriguez Luna, Eduardo Salvador Lopez Hernandez, Antonio Fernandez Crispin, Maria de los Angeles Chamorro Zarate","doi":"10.59879/oyvo2","DOIUrl":"https://doi.org/10.59879/oyvo2","url":null,"abstract":"Climate change (CC) implies recent, rapid and more intense changes in climate. Its effects are reflected by the planet's natural processes and in human activities that impact socioeconomic and environmental systems. The research objective was to identify the perception of CC of the inhabitants of Cúlico 2nd Section, Huimango 1st Section and ejido La Chonita, through the Correspondence Analysis (CA) and vulnerability elements, estimating the criteria of Exposure (E), Sensitivity (S) and Adaptive Capacity (CA) that allows strengthening, through social participation, the capacities and values of the population. The study area is located near oil fields that generate environmental impacts, mainly on cocoa (Theobroma cacao) and corn (Zea mays) crops. A qualitative and quantitative analysis was carried out on a sample of 180 individuals. The results suggest that the population is exposed to the consequences of climatic events and degradation of natural resources, that there is sensitivity in their productive systems to diseases and in the quality of basic services, which limits the capacity for adequate response; it is important to generate actions to address local vulnerability, to strengthen the capacities and socio-environmental values of the population and to implement mitigation and adaptation actions, based on social participation and the formation of collaborative networks with other communities","PeriodicalId":49454,"journal":{"name":"Sylwan","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135612114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Greenhouse effect carbon emission control has seriously affected world shipping, and the choice of alternative energy sources has become a challenging task. To meet this task, a variety of technologies and energy developments are essential for reducing carbon emissions associated with shipping. The search for the best maritime fuel has been a lengthy process, and at this stage, the global shipping industry is primarily facing a number of alternative energy sources with only limited carbon reduction capacity and high infrastructure investment. This study conducts a questionnaire survey of the world's major container, bulk, and tanker operators from the perspective of the industry, using technological, economic, environmental, societal, and fuel scalability factors to construct an analytical model of the impact of energy choices and the optimal fuel mix during the zero-carbon transitional period. FAHP and FTOPSIS were used to explore the objective opinions of container, bulk, and tanker operators regarding their energy mix during the zero-carbon transition period. The study results show that "fuel legality" is the key influencing factor and that "synthetic fuel" and "solar cells" are the most suitable possibilities as a carbon reduction combination of an alternative fuel and renewable auxiliary energy respectively at this stage of maritime transportation.
{"title":"Analysis of the Best Fuel Mix for Shipping during the Zero Carbon Transition","authors":"Tien-Chun Ho, Hsuan-Shih Lee","doi":"10.59879/tepxm","DOIUrl":"https://doi.org/10.59879/tepxm","url":null,"abstract":"Greenhouse effect carbon emission control has seriously affected world shipping, and the choice of alternative energy sources has become a challenging task. To meet this task, a variety of technologies and energy developments are essential for reducing carbon emissions associated with shipping. The search for the best maritime fuel has been a lengthy process, and at this stage, the global shipping industry is primarily facing a number of alternative energy sources with only limited carbon reduction capacity and high infrastructure investment. This study conducts a questionnaire survey of the world's major container, bulk, and tanker operators from the perspective of the industry, using technological, economic, environmental, societal, and fuel scalability factors to construct an analytical model of the impact of energy choices and the optimal fuel mix during the zero-carbon transitional period. FAHP and FTOPSIS were used to explore the objective opinions of container, bulk, and tanker operators regarding their energy mix during the zero-carbon transition period. The study results show that \"fuel legality\" is the key influencing factor and that \"synthetic fuel\" and \"solar cells\" are the most suitable possibilities as a carbon reduction combination of an alternative fuel and renewable auxiliary energy respectively at this stage of maritime transportation.","PeriodicalId":49454,"journal":{"name":"Sylwan","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135495494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
It is important for a contractor to know which points should be emphasized when negotiating a project, and what factors need to be considered in order to ensure that the project will be as successful as possible. This research focuses on effective project management within construction projects, and the factors that affect project success. This was done by looking at two similar projects executed at the same time with two different project managers. One client was a non-profit organization run without profit goals, and the other client was a real estate development company with investment in mind. The works started in a different way, as one project took part in the design phase from the beginning and had a fixed unit price, while the other consisted only of the execution of the project and a cost-plus contract. The results of the projects turned out to be different in terms of schedules and profits. One client has continued to use the relevant contractor for many other projects, while the other client did not want to continue working with the contractor. Qualitative methodology was used during the research and enabled the researcher to gain deeper insight into the experience of the project managers in their work. Information was also obtained about the tools that the project managers used to secure the project's finances, schedules, quality, and other important issues. Two interviews were conducted with senior project managers in the team. The answers given by the project managers were then compared and analysed to determine what caused their projects to produce the results they did. The main findings involved the importance of positive communication and trust, especially between contractors and the client, but also within the overall project, within the team, subcontractors, suppliers, and designers. Another factor that greatly affected the success of the projects was organisation, including the recording of data, whether it was about schedules and the processes followed to meet a specific schedule; or financial management, including keeping track of additional work and deviations, as these items are often costly and come up in the end of the project when the settlement begins on unresolved items. At the same time, keeping track of the quality of the project is also important, as is, again, recording reviews, deviations, and mistakes, as they can be both costly and time-consuming.
{"title":"Success Factors in Construction Project Management","authors":"Unnur Maria Hardardottir, Edvald Moller","doi":"10.59879/yz9ua","DOIUrl":"https://doi.org/10.59879/yz9ua","url":null,"abstract":"It is important for a contractor to know which points should be emphasized when negotiating a project, and what factors need to be considered in order to ensure that the project will be as successful as possible. This research focuses on effective project management within construction projects, and the factors that affect project success. This was done by looking at two similar projects executed at the same time with two different project managers. One client was a non-profit organization run without profit goals, and the other client was a real estate development company with investment in mind. The works started in a different way, as one project took part in the design phase from the beginning and had a fixed unit price, while the other consisted only of the execution of the project and a cost-plus contract. The results of the projects turned out to be different in terms of schedules and profits. One client has continued to use the relevant contractor for many other projects, while the other client did not want to continue working with the contractor. Qualitative methodology was used during the research and enabled the researcher to gain deeper insight into the experience of the project managers in their work. Information was also obtained about the tools that the project managers used to secure the project's finances, schedules, quality, and other important issues. Two interviews were conducted with senior project managers in the team. The answers given by the project managers were then compared and analysed to determine what caused their projects to produce the results they did. The main findings involved the importance of positive communication and trust, especially between contractors and the client, but also within the overall project, within the team, subcontractors, suppliers, and designers. Another factor that greatly affected the success of the projects was organisation, including the recording of data, whether it was about schedules and the processes followed to meet a specific schedule; or financial management, including keeping track of additional work and deviations, as these items are often costly and come up in the end of the project when the settlement begins on unresolved items. At the same time, keeping track of the quality of the project is also important, as is, again, recording reviews, deviations, and mistakes, as they can be both costly and time-consuming.","PeriodicalId":49454,"journal":{"name":"Sylwan","volume":"1 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71244474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Supporting undergraduate students is important to ensure student success especially in using the Learning Management Systems (LMS). The case study research reviewed literature of student support, Open Distance and eLearning (ODeL), challenges and strategies for student support in ODeL context. The aim of the study was to investigate student support in ODeL context. The aim of of the study was to investigate student support in ODeL. The case study was designed to draw from qualitative research so as to deepen the understanding of student support in ODeL context. Purposive sampling was used to interview 7 lecturers as participants from a total number of about 30 lecturers. The researcher adopted Garrison, Anderson and Archer's Community of Inquiry framework to study the case in - depth. The findings suggested that some lecturers do not have the necessary skills to support student on the learning management. Nevetherless, some participants interviewed do not have qualifications in online learning. More importantly, the selected institution had adopted ODeL to promote access of higher education at the business school. Some of the challenges that the institution is experiencing is the lack of internet connectivity on the LMS. Workload is sometimes hampering lecturers to support students on the LMS. The study has recommended that academics should be trained on strategies and approaches to support students in ODeL. Therefore, training lecturers in new technologies should also be considered. In conclusion , student support is the cornerstone of distance education in higher education institutions.
{"title":"Supporting undergraduate students in selected Open Distance and eLearning institution.","authors":"G. Baloyi","doi":"10.59879/5sf6w","DOIUrl":"https://doi.org/10.59879/5sf6w","url":null,"abstract":"Supporting undergraduate students is important to ensure student success especially in using the Learning Management Systems (LMS). The case study research reviewed literature of student support, Open Distance and eLearning (ODeL), challenges and strategies for student support in ODeL context. The aim of the study was to investigate student support in ODeL context. The aim of of the study was to investigate student support in ODeL. The case study was designed to draw from qualitative research so as to deepen the understanding of student support in ODeL context. Purposive sampling was used to interview 7 lecturers as participants from a total number of about 30 lecturers. The researcher adopted Garrison, Anderson and Archer's Community of Inquiry framework to study the case in - depth. The findings suggested that some lecturers do not have the necessary skills to support student on the learning management. Nevetherless, some participants interviewed do not have qualifications in online learning. More importantly, the selected institution had adopted ODeL to promote access of higher education at the business school. Some of the challenges that the institution is experiencing is the lack of internet connectivity on the LMS. Workload is sometimes hampering lecturers to support students on the LMS. The study has recommended that academics should be trained on strategies and approaches to support students in ODeL. Therefore, training lecturers in new technologies should also be considered. In conclusion , student support is the cornerstone of distance education in higher education institutions.","PeriodicalId":49454,"journal":{"name":"Sylwan","volume":"1 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71244661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Peroral endoscopic myotomy (POEM) is one of the standard treatment modality for achalasia. This study was to evaluate the usefulness of timed barium esophagography (TBE) in the evaluation of treatment effect of POEM for achalasia. A total of 36 patients (M:F=22:14) underwent pre- and post-POEM TBE (3 groups according to lower esophageal sphincter (LES) caliber, A: < 5 mm, B: 5~8 mm, C: > 8 mm). On pre and post-POEM TBE, the rate of area changes of barium column and the changes of LES caliber were investigated. All data were statistically analyzed using the Kruskal-Wallis test or Mann-Whitney U test. The mean rate of area change of the barium column at 5 minutes between pre- and post-POEM TBE were -51.7%, -28.8% and -11.6% in group A (n=10), B (n=18), and C (n=8), respectively, statistically significant (p < 0.001). The rate difference of the barium column area changes between group A and group B only showed the statistical significance (p < 0.001). The mean increased caliber of LES after POEM was 5.5 mm, 2.9 mm, and 3.3 mm in group A, B, and C, respectively. Group A and bird’s beak type showed a statistically significant treatment effect (p < 0.001). In conclusion, TBE was useful in the evaluation of the treatment effect of POEM for achalasia and the narrowest LES group and bird’s beak esophageal type on TBE showed statistically significant treatment effects.
{"title":"Efficacy of Peroral Endoscopic Myotomy for Achalasia: Evaluation of Treatment Effect using Timed Barium Esophagography","authors":"Jae-Joon Chung, Eun-Suk Cho, Joo Hee Kim","doi":"10.59879/4ppre","DOIUrl":"https://doi.org/10.59879/4ppre","url":null,"abstract":"Peroral endoscopic myotomy (POEM) is one of the standard treatment modality for achalasia. This study was to evaluate the usefulness of timed barium esophagography (TBE) in the evaluation of treatment effect of POEM for achalasia. A total of 36 patients (M:F=22:14) underwent pre- and post-POEM TBE (3 groups according to lower esophageal sphincter (LES) caliber, A: < 5 mm, B: 5~8 mm, C: > 8 mm). On pre and post-POEM TBE, the rate of area changes of barium column and the changes of LES caliber were investigated. All data were statistically analyzed using the Kruskal-Wallis test or Mann-Whitney U test. The mean rate of area change of the barium column at 5 minutes between pre- and post-POEM TBE were -51.7%, -28.8% and -11.6% in group A (n=10), B (n=18), and C (n=8), respectively, statistically significant (p < 0.001). The rate difference of the barium column area changes between group A and group B only showed the statistical significance (p < 0.001). The mean increased caliber of LES after POEM was 5.5 mm, 2.9 mm, and 3.3 mm in group A, B, and C, respectively. Group A and bird’s beak type showed a statistically significant treatment effect (p < 0.001). In conclusion, TBE was useful in the evaluation of the treatment effect of POEM for achalasia and the narrowest LES group and bird’s beak esophageal type on TBE showed statistically significant treatment effects.","PeriodicalId":49454,"journal":{"name":"Sylwan","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135495659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
During the manufacturing process of electronic products, one of the most critical stages is the soldering of components onto the printed circuit board (PCB). Even a minor defect in the PCB can lead to significant issues in the final product. Therefore, a rigorousndefect inspection process is employed during manufacturing, which can be categorized into manual inspection and automated optical inspection (AOI). Manual inspection suffers from drawbacks such as slow speed and the expenditure of manpower and costs. Hence, most manufacturers opt for automated optical inspection to expedite production. However, most current automated optical inspection systems rely on traditional optical inspection algorithms. These computational methods are susceptible to variations in lighting conditions caused by slight differences in the placement of PCBs or the amount of solder. Consequently, these variations often result in misjudgments, where qualified PCBs are mistakenly categorized as defective, leading to high false positive rates in AOI systems.nThis paper presents a deep learning based method for PCB defect detection. The proposed approach involves the creation of two separate models for classifying defective components individually. Once both models demonstrate a basic recognition capability, they are combined into a master model using the method proposed in this study to enhance overall recognition accuracy. The model hasnbeen trained on datasets for capacitors and resistors, and the experimental results indicate an accuracy of over 99% for both component types.
{"title":"Intelligent Print Circuit Board Defect Detection","authors":"Huang-Chu Huang, Chih-Yung Chen, I-Chun Chen, Rey-Chue Hwang","doi":"10.59879/gbzfq","DOIUrl":"https://doi.org/10.59879/gbzfq","url":null,"abstract":"During the manufacturing process of electronic products, one of the most critical stages is the soldering of components onto the printed circuit board (PCB). Even a minor defect in the PCB can lead to significant issues in the final product. Therefore, a rigorousndefect inspection process is employed during manufacturing, which can be categorized into manual inspection and automated optical inspection (AOI). Manual inspection suffers from drawbacks such as slow speed and the expenditure of manpower and costs. Hence, most manufacturers opt for automated optical inspection to expedite production. However, most current automated optical inspection systems rely on traditional optical inspection algorithms. These computational methods are susceptible to variations in lighting conditions caused by slight differences in the placement of PCBs or the amount of solder. Consequently, these variations often result in misjudgments, where qualified PCBs are mistakenly categorized as defective, leading to high false positive rates in AOI systems.nThis paper presents a deep learning based method for PCB defect detection. The proposed approach involves the creation of two separate models for classifying defective components individually. Once both models demonstrate a basic recognition capability, they are combined into a master model using the method proposed in this study to enhance overall recognition accuracy. The model hasnbeen trained on datasets for capacitors and resistors, and the experimental results indicate an accuracy of over 99% for both component types.","PeriodicalId":49454,"journal":{"name":"Sylwan","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135611735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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