This article provides an analysis of the wire electrical discharge machining (EDM) process. The causes of wire vibration, bowing, and breakage are identified. The cross sectional configuration of an eroded wire is derived from basic physics under the assumption that the erosion rate is constant. This configuration is verified experimentally with further explanation as to why numerous experimental studies have yielded different configurations. A computational model has been developed that can evaluate the systematic effects that lead to wire breakage by determining the stress induced by wire erosion and the stress induced by the sparks during the operation of a wire-cutting EDM machine. This model is also capable of determining the extent of wire bowing and vibrations in these machines but only in the frontal direction. The model is supported by data from experiments performed on an AGIECUT 612 wire machine cutting a 10 mm high copper bar with a 0.15 mm brass wire to acquire wire breakage data. The nearly parabolic shape of the bowed wire agrees with the results of other authors making more restrictive assumptions.

Osilasi berdasarkan redamannya terbagi menjadi tiga yaitu osilasi teredam ringan, teredam kritis dan teredam penuh. Penelitian ini menyelidiki fenomena osilasi teredam yang disebabkan oleh fluida pada beban yang digantungkan pada pegas. Metode yang digunakan adalah metode eksperimen dan analisis grafik. Pengambilan data dilakukan dengan menggunakan software Video Analysis Tracker. Hasil penelitian menunjukan gerakan osilasi teredam kritis terjadi pada beban yang digantungkan pada pegas dalam medium air. Osilasi beban dalam medium minyak mengakibatkan redaman penuh. Sedangkan osilasi beban dalam medium udara dapat mengakibatkan redaman ringan.

Student knowledge criteria is one aspect that shows the success of a learning process. According to pedagogy subject matter, learning is successful if the students’ knowledge has reached the fruitful criteria. This research aims to determine the formative assessment of fruitful criteria in work and energy learning based on directing motives and syntactic aspects. The research method used is qualitative with a case study approach. Data were analyzed using discourse analysis. Sample of this research are teacher and students at one school in the Bandung district was conducted on the teaching motives of educators, aspects of teaching materials and formative assessment used in learning activities with data collection techniques in the form of direct and indirect observation using a video recorder with an observation sheet and indicator motives, aspects and criteria sheet. The analysis is done by making a transcript of learning activities, making basic texts with refinement, preparing micro and macro propositions so that the learning macro structure is obtained. Furthermore, the analysis is carried out with reference to the indicators of each motif, aspect, and criteria. The results showed there were six formative assessment questions of fruitful criteria based on directing motives and syntactic aspects or appears at 37.5% of the total fruitful criteria formative assessment. The researcher suggests doing research on other criteria so that it can be known in full the types of questions for formative assessment based on the pedagogy subject matter approach.

The construction of the Industrial Engineering Department building is an effort to support the educational infrastructure at Andalas University. However, the building construction process was stopped because the contractor had terminated the contract (breach of contract) and it took a long time to continue the construction. Before that, a structural evaluation of the building structure should be conducted due to the update of the building standards. In this study, the structural evaluation was carried out by analyzing and modelling the building using ETABS v.18 software, as well as loading analysis on the building regarding current Indonesian building standards such as SNI 1726-2019 for earthquake resistance building design, SNI 2847-2019 for requirements of the structural concrete building and SNI 1727-2020 for building minimum design loads. The results of the analysis show that several structural beams did not have a strong enough capacity to withstand the working loads, where the ultimate moment and shear values due to the influence of acting loads were more than the nominal moments and shear values. Retrofitting of the weak structural beams using the CFRP wrapping method was recommended to improve the structural capacity of the building.