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Assessments of new pedagogical practices usually rely on instructor oriented surveys and questionnaires to measure student perceptions of teaching methods; however, fixed response categories in structured questionnaires might bias results. This paper demonstrates a mixed methods approach using open and multi-dimensional scaling (MDS) for a student-oriented exploratory analysis and visualization of perceptions of teaching methods. A scientific writing and research methodology course is a required course for first year PhD students in software engineering and geo-infomatics at Wuhan University, China. PhD students attending this course came from countries whose first language is not English, and from a variety of software engineering and geo-infomatics domains. The problem therefore, was to elicit un-mediated perceptions of course assignment, reduce and generalize the resulting data for interpretation. A graphical visualization of themes emerging in student responses to two open-ended questions about an assignment provided a basis for inferring student interests and needs. In this course, an assessment of a task oriented problem-solving experience was implemented through a mixed method strategy incorporating qualitative methods, exploratory data mining techniques, and cartographic visualization. The visualization shows that participating students generally perceived the exercise as challenging, helped them understand journal requirements, and develop ways to survey texts to extract information. The results also suggested that this consensus breaks down in terms of each participant's own goals, domain, and research interests. Unstructured questions, open coding, and MDS visualization might also prove to be helpful in the process of devising and assessing other student centered pedagogies.

Abstract In transmission lines, shunt‐reactors are commonly applied to counteract the “Ferranti effect.” However, in highly compensated lines, hazardous overvoltage may occur during unbalanced open‐phase conditions. In addition, when a new substation is put into operation, π circuit can be selected by accessing an existing transmission line and the original shunt‐reactor configuration is maintained. Severe overvoltage may occur on the shunt‐reactor side of the newly installed transmission line. In this study, we analysed the effects of compensation, neutral‐reactor, and system frequency on open‐phase overvoltage. The maximum deviation of system frequency is

The uniqueness of DC deep-well ground electrodes (DWGEs) lies in their low area requirements. However, the gas produced by DWGEs during electrolysis may cause more severe exhaust problems than those caused by conventional electrodes. To investigate the influence of different electrode materials on the gas evolution of DWGEs, an innovative U-shaped experimental platform is proposed for the separate collection of cathode and anode gases. The metal–electrolyte contact interface in a DWGE project was simulated, and gas evolution experiments were performed on three typical ground electrode materials. The gas evolution rates of the electrode materials when operate as cathodes and anodes were obtained. Polarization curves were used to compare the corrosion rates of the three materials and evaluate the effects of these rates on the gas evolution rates of the materials. The results revealed that when operated as anodes, mixed metal oxide (MMO) and high-silicon cast iron produced oxygen, whereas carbon steel did not. Furthermore, the evolution of O2 in MMO was faster than that in high-silicon cast iron. When operated as cathodes, the three materials generated hydrogen, and carbon steel exhibited the slowest H2 evolution rate. The current distribution in the different gas evolution processes was summarized. The supplied current was used as the reaction current of metal corrosion and for gas generation. Under the same current, quicker corrosion corresponded to a lower amount of gas evolution for a material. [ABSTRACT FROM AUTHOR]