随着电网规模扩大和电力元件不断增加,电力系统检修方式变得日趋复杂,仅依靠传统方法难以对海量检修方式下电网的低频振荡风险进行评估。针对此问题,提出了一种基于长短期记忆(long short term memory,LSTM)神经网络的检修态电网低频振...随着电网规模扩大和电力元件不断增加,电力系统检修方式变得日趋复杂,仅依靠传统方法难以对海量检修方式下电网的低频振荡风险进行评估。针对此问题,提出了一种基于长短期记忆(long short term memory,LSTM)神经网络的检修态电网低频振荡风险预测方法。首先,提出了电力系统检修方式的统一编码方法,使计算机能够快速、准确识别电网在各种检修方式下的运行状态;然后,基于同步相量测量单元(phasor measurement unit,PMU)实时测量的电网历史运行数据,利用LSTM神经网络对不同检修方式下电网的低频振荡次数进行预测,从而评估检修态电网发生低频振荡的风险;最后,以华中地区某省级电网为算例,验证了所提方法的准确性和快速性。展开更多
To simulate the intense bunched beam transport, a computer program LEADS-3D has been developed. The particle trajectories are analysed with the Lie algebraic method. The third order approximation of the trajectory sol...To simulate the intense bunched beam transport, a computer program LEADS-3D has been developed. The particle trajectories are analysed with the Lie algebraic method. The third order approximation of the trajectory solutions is made with space charge forces off, and the second order approximation is made with space charge forces on. The particle distribution in the 3D ellipsoid is uniform or Gaussian. Most of the conventional beam optical elements are incorporated in the code. The optimization procedures are provided to fit the beam lines to satisfy the given optical conditions.展开更多
The availability of automated evaluation methodologies that may reliably be used for determining students’ scholastic performance through assigning letter grades are of utmost practical importance to educators, stude...The availability of automated evaluation methodologies that may reliably be used for determining students’ scholastic performance through assigning letter grades are of utmost practical importance to educators, students, and do invariably have pivotal values to all stakeholders of the academic process. In particular, educators use letter grades as quantification metrics to monitor students’ intellectual progress within a framework of clearly specified learning objectives of a course. To students grades may be used as predictive measures and motivating drives for success in a study field. However due to numerous objective and subjective variables that may by be accounted for in a methodological process of assigning students’ grades, and since such a process is often tainted with personal philosophy and human psychology factors, it is essential that educators exercise extra care in maximizing positive account of all objective factors and minimizing negative ramifications of subjectively fuzzy factors. To this end, and in an attempt to make assigning students’ grades more reliable for assessing true-level of mastering specified learning outcomes, this paper will: i) provide a literature review on previous works on the most common methods that have traditionally been in use for assigning students’ grades, and a short account of the virtues and/or vices of such methods, and ii) present a user-friendly computer code that may be easily adapted for the purpose of assigning students’ grades. This would relieve educators from the overwhelming concerns associated with mechanistic aspects of determining educational metrics, and it would allow them to have more time and focus to obtain reliable assessments of true-level of students’ mastery of learning outcomes by accounting for all possible evaluation components.展开更多
Traditionally computer sciences courses will assess software code.It is common and accepted good practice(as in written reports) to reference other sources of appropriate material.However there appears to be no explic...Traditionally computer sciences courses will assess software code.It is common and accepted good practice(as in written reports) to reference other sources of appropriate material.However there appears to be no explicit method,recommendation or advice available to computer science tutors and students on a referencing approach! This paper aims to stimulate discussion from peers involved in software engineering education.By discussing the apparent lack of "referencing within code" advice to students and proposing suggestions for appropriate solutions.This will be based on the authors' experience of assessing code and the current advice given to their students.展开更多
文摘随着电网规模扩大和电力元件不断增加,电力系统检修方式变得日趋复杂,仅依靠传统方法难以对海量检修方式下电网的低频振荡风险进行评估。针对此问题,提出了一种基于长短期记忆(long short term memory,LSTM)神经网络的检修态电网低频振荡风险预测方法。首先,提出了电力系统检修方式的统一编码方法,使计算机能够快速、准确识别电网在各种检修方式下的运行状态;然后,基于同步相量测量单元(phasor measurement unit,PMU)实时测量的电网历史运行数据,利用LSTM神经网络对不同检修方式下电网的低频振荡次数进行预测,从而评估检修态电网发生低频振荡的风险;最后,以华中地区某省级电网为算例,验证了所提方法的准确性和快速性。
基金Project supported by the National Natural Science Foundation of China (Grant No. 10975011)the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20070001001)
文摘To simulate the intense bunched beam transport, a computer program LEADS-3D has been developed. The particle trajectories are analysed with the Lie algebraic method. The third order approximation of the trajectory solutions is made with space charge forces off, and the second order approximation is made with space charge forces on. The particle distribution in the 3D ellipsoid is uniform or Gaussian. Most of the conventional beam optical elements are incorporated in the code. The optimization procedures are provided to fit the beam lines to satisfy the given optical conditions.
文摘The availability of automated evaluation methodologies that may reliably be used for determining students’ scholastic performance through assigning letter grades are of utmost practical importance to educators, students, and do invariably have pivotal values to all stakeholders of the academic process. In particular, educators use letter grades as quantification metrics to monitor students’ intellectual progress within a framework of clearly specified learning objectives of a course. To students grades may be used as predictive measures and motivating drives for success in a study field. However due to numerous objective and subjective variables that may by be accounted for in a methodological process of assigning students’ grades, and since such a process is often tainted with personal philosophy and human psychology factors, it is essential that educators exercise extra care in maximizing positive account of all objective factors and minimizing negative ramifications of subjectively fuzzy factors. To this end, and in an attempt to make assigning students’ grades more reliable for assessing true-level of mastering specified learning outcomes, this paper will: i) provide a literature review on previous works on the most common methods that have traditionally been in use for assigning students’ grades, and a short account of the virtues and/or vices of such methods, and ii) present a user-friendly computer code that may be easily adapted for the purpose of assigning students’ grades. This would relieve educators from the overwhelming concerns associated with mechanistic aspects of determining educational metrics, and it would allow them to have more time and focus to obtain reliable assessments of true-level of students’ mastery of learning outcomes by accounting for all possible evaluation components.
文摘Traditionally computer sciences courses will assess software code.It is common and accepted good practice(as in written reports) to reference other sources of appropriate material.However there appears to be no explicit method,recommendation or advice available to computer science tutors and students on a referencing approach! This paper aims to stimulate discussion from peers involved in software engineering education.By discussing the apparent lack of "referencing within code" advice to students and proposing suggestions for appropriate solutions.This will be based on the authors' experience of assessing code and the current advice given to their students.