数据可视化的完整流程包括数据采集、数据处理、数据分析及数据可视化4个环节。该文展示使用Power BI Desktop对豆瓣电影TOP250评分数据,进行多页面Web获取、处理及可视化展示的应用案例。首先,使用Power BI Desktop的M语言创建查询函数...数据可视化的完整流程包括数据采集、数据处理、数据分析及数据可视化4个环节。该文展示使用Power BI Desktop对豆瓣电影TOP250评分数据,进行多页面Web获取、处理及可视化展示的应用案例。首先,使用Power BI Desktop的M语言创建查询函数,通过添加列选择调用自定义函数,实现多页面Web数据源的连接与获取。接着,通过数据转换功能执行字段提取与数据类型转换,最终得到包含电影排名、名称、评分和上映年份等关键字段的数据表。最后,基于250部电影的评分数据创建数据可视化内容,包括柱形图、电影得分切片器及影片信息矩阵表格,根据电影评分数据为柱形图设置颜色递进效果,对切片器和影片信息矩阵表格添加联动效应,达到交互式的效果。展开更多
As cataract surgery progresses from “restoration of sight” to “refractive correction”, precise prediction of intraocular lens (IOL) power is critical for enhancing postoperative visual quality in patients. IOL pow...As cataract surgery progresses from “restoration of sight” to “refractive correction”, precise prediction of intraocular lens (IOL) power is critical for enhancing postoperative visual quality in patients. IOL power calculation methods have evolved and innovated throughout time, from early theoretical and regression formulas to nonlinear formulas for estimating effective lens position (ELP), multivariable formulas, and innovative formulas that use optical principles and AI-based online formulas. This paper thoroughly discusses the development and iteration of traditional IOL calculation formulas, the emergence of new IOL calculation formulas, and the selection of IOL calculation formulas for different patients in the era of refractive cataract surgery, serving as a reference for “personalized” IOL implantation in clinical practice.展开更多
In light of the increasing recognition of the necessity to evaluate and mitigate the environmental impact of human activities, the aim of this study is to assess the greenhouse gases emitted in 2022 by the Kossodo the...In light of the increasing recognition of the necessity to evaluate and mitigate the environmental impact of human activities, the aim of this study is to assess the greenhouse gases emitted in 2022 by the Kossodo thermal power plant as a consequence of its electricity production. The specific objective was to identify the emission sources and quantify the gases generated, with the purpose of proposing effective solutions for reducing the plant’s ecological footprint. In order to achieve the objectives set out in the study, the Bilan Carbone® method was employed. Following an analysis of the plant’s activities, seven emission items were identified as requiring further investigation. The data was gathered from the plant’s activity reports, along with measurements and questionnaires distributed to employees. The data collected was subjected to processing in order to produce the sought activity data. The Bilan Carbone® V7.1 spreadsheet was employed to convert the activity data into equivalent quantities of CO2. The full assessment indicates that the majority of the power plant’s emissions come from the combustion of HFO and DDO, accounting for 96.11% of the Kossodo power plant’s total GHG emissions in 2022. The plant produced 280,585,676 kilowatt-hours (kWh), resulting in emissions of 218,492.785 ± 10,924.639 tCO2e, which yielded an emission factor of 0.78 kgCO2e/kWh for the year 2022. In order to reduce this rate, recommendations for improved energy efficiency have been issued to management and all staff.展开更多
This paper presents an optimized strategy for multiple integrations of photovoltaic distributed generation (PV-DG) within radial distribution power systems. The proposed methodology focuses on identifying the optimal ...This paper presents an optimized strategy for multiple integrations of photovoltaic distributed generation (PV-DG) within radial distribution power systems. The proposed methodology focuses on identifying the optimal allocation and sizing of multiple PV-DG units to minimize power losses using a probabilistic PV model and time-series power flow analysis. Addressing the uncertainties in PV output due to weather variability and diurnal cycles is critical. A probabilistic assessment offers a more robust analysis of DG integration’s impact on the grid, potentially leading to more reliable system planning. The presented approach employs a genetic algorithm (GA) and a determined PV output profile and probabilistic PV generation profile based on experimental measurements for one year of solar radiation in Cairo, Egypt. The proposed algorithms are validated using a co-simulation framework that integrates MATLAB and OpenDSS, enabling analysis on a 33-bus test system. This framework can act as a guideline for creating other co-simulation algorithms to enhance computing platforms for contemporary modern distribution systems within smart grids concept. The paper presents comparisons with previous research studies and various interesting findings such as the considered hours for developing the probabilistic model presents different results.展开更多
In order to increase the stability of the Mongolia power system, a single-phase automatic reclosing device (SPAR) was introduced on double-circuit power lines built with a size of 330 kV, operating on a voltage of 220...In order to increase the stability of the Mongolia power system, a single-phase automatic reclosing device (SPAR) was introduced on double-circuit power lines built with a size of 330 kV, operating on a voltage of 220 kV and a length of 250 km. These overhead power lines (L-213, L-214) connect the 220/110/35 kV “Songino” substation with the “Mandal” substation and form system networks. This paper presents the challenges encountered when implementing single-phase automatic reclosing (SPAR) devices and compares the changes in power system parameters before and after SPAR deployment for a long 220 kV line. Simulations and analyses were carried out using DIgSILENT PowerFactory software, focusing on rotor angle stability, and the overall impact on the power system during short-circuit faults. The evaluation also utilized measurement data from the Wide Area Monitoring System (WAMS) to compare system behavior pre- and post-implementation of SPAR. The findings reveal that SPAR significantly enhances system reliability and stability, effectively mitigating the risk of oscillations and stability loss triggered by short circuits. This improvement contributes to a more resilient power system, reducing the potential for disturbances caused by faults.展开更多
文摘数据可视化的完整流程包括数据采集、数据处理、数据分析及数据可视化4个环节。该文展示使用Power BI Desktop对豆瓣电影TOP250评分数据,进行多页面Web获取、处理及可视化展示的应用案例。首先,使用Power BI Desktop的M语言创建查询函数,通过添加列选择调用自定义函数,实现多页面Web数据源的连接与获取。接着,通过数据转换功能执行字段提取与数据类型转换,最终得到包含电影排名、名称、评分和上映年份等关键字段的数据表。最后,基于250部电影的评分数据创建数据可视化内容,包括柱形图、电影得分切片器及影片信息矩阵表格,根据电影评分数据为柱形图设置颜色递进效果,对切片器和影片信息矩阵表格添加联动效应,达到交互式的效果。
文摘As cataract surgery progresses from “restoration of sight” to “refractive correction”, precise prediction of intraocular lens (IOL) power is critical for enhancing postoperative visual quality in patients. IOL power calculation methods have evolved and innovated throughout time, from early theoretical and regression formulas to nonlinear formulas for estimating effective lens position (ELP), multivariable formulas, and innovative formulas that use optical principles and AI-based online formulas. This paper thoroughly discusses the development and iteration of traditional IOL calculation formulas, the emergence of new IOL calculation formulas, and the selection of IOL calculation formulas for different patients in the era of refractive cataract surgery, serving as a reference for “personalized” IOL implantation in clinical practice.
文摘In light of the increasing recognition of the necessity to evaluate and mitigate the environmental impact of human activities, the aim of this study is to assess the greenhouse gases emitted in 2022 by the Kossodo thermal power plant as a consequence of its electricity production. The specific objective was to identify the emission sources and quantify the gases generated, with the purpose of proposing effective solutions for reducing the plant’s ecological footprint. In order to achieve the objectives set out in the study, the Bilan Carbone® method was employed. Following an analysis of the plant’s activities, seven emission items were identified as requiring further investigation. The data was gathered from the plant’s activity reports, along with measurements and questionnaires distributed to employees. The data collected was subjected to processing in order to produce the sought activity data. The Bilan Carbone® V7.1 spreadsheet was employed to convert the activity data into equivalent quantities of CO2. The full assessment indicates that the majority of the power plant’s emissions come from the combustion of HFO and DDO, accounting for 96.11% of the Kossodo power plant’s total GHG emissions in 2022. The plant produced 280,585,676 kilowatt-hours (kWh), resulting in emissions of 218,492.785 ± 10,924.639 tCO2e, which yielded an emission factor of 0.78 kgCO2e/kWh for the year 2022. In order to reduce this rate, recommendations for improved energy efficiency have been issued to management and all staff.
文摘This paper presents an optimized strategy for multiple integrations of photovoltaic distributed generation (PV-DG) within radial distribution power systems. The proposed methodology focuses on identifying the optimal allocation and sizing of multiple PV-DG units to minimize power losses using a probabilistic PV model and time-series power flow analysis. Addressing the uncertainties in PV output due to weather variability and diurnal cycles is critical. A probabilistic assessment offers a more robust analysis of DG integration’s impact on the grid, potentially leading to more reliable system planning. The presented approach employs a genetic algorithm (GA) and a determined PV output profile and probabilistic PV generation profile based on experimental measurements for one year of solar radiation in Cairo, Egypt. The proposed algorithms are validated using a co-simulation framework that integrates MATLAB and OpenDSS, enabling analysis on a 33-bus test system. This framework can act as a guideline for creating other co-simulation algorithms to enhance computing platforms for contemporary modern distribution systems within smart grids concept. The paper presents comparisons with previous research studies and various interesting findings such as the considered hours for developing the probabilistic model presents different results.
文摘In order to increase the stability of the Mongolia power system, a single-phase automatic reclosing device (SPAR) was introduced on double-circuit power lines built with a size of 330 kV, operating on a voltage of 220 kV and a length of 250 km. These overhead power lines (L-213, L-214) connect the 220/110/35 kV “Songino” substation with the “Mandal” substation and form system networks. This paper presents the challenges encountered when implementing single-phase automatic reclosing (SPAR) devices and compares the changes in power system parameters before and after SPAR deployment for a long 220 kV line. Simulations and analyses were carried out using DIgSILENT PowerFactory software, focusing on rotor angle stability, and the overall impact on the power system during short-circuit faults. The evaluation also utilized measurement data from the Wide Area Monitoring System (WAMS) to compare system behavior pre- and post-implementation of SPAR. The findings reveal that SPAR significantly enhances system reliability and stability, effectively mitigating the risk of oscillations and stability loss triggered by short circuits. This improvement contributes to a more resilient power system, reducing the potential for disturbances caused by faults.