scholarly journals Investigating student understanding of a heat engine: a case study of a Stirling engine

2021 ◽  
Vol 57 (1) ◽  
pp. 015011
Author(s):  
Lilin Zhu ◽  
Gang Xiang
Keyword(s):  
Heat Engine ◽  
Stirling Engine ◽  
Engineering Knowledge ◽  
Stirling Cycle ◽  
Student Difficulties ◽  
Error Ratio ◽  
Post Test ◽  
Method Of Measurement ◽  
Engineering Training

Abstract We report on the study of student difficulties regarding a heat engine in the context of a Stirling cycle by the method of measurement. An in-class test about a Stirling engine with a regenerator was taken by three classes, and the students were asked to perform one of the most basic activities—calculate the efficiency of the heat engine. Our data indicate that quite a few students have not developed a robust conceptual understanding of basic engineering knowledge of the heat engine. Notably, the error ratio of the class given a simple tutorial of engineering knowledge is smaller than those of the other two classes by more than 20%. In addition, both the written answers and post-test interviews show that most of the students cannot associate Carnot’s theorem with a Stirling cycle. Our results suggest that both scientific and engineering knowledge are important and should be included in instructional approaches, especially in the thermodynamics course taught in the countries and regions with a tradition of not paying much attention to experimental education or engineering training.

Valved Heat Engine Working on Modified Atkinson Cycle

2010 ◽  
Vol 132 (1) ◽  
Author(s):  
C. V. Ramesh
Keyword(s):  
Thermal Efficiency ◽  
Heat Engine ◽  
Engine Performance ◽  
Inertial Force ◽  
Expansion Ratio ◽  
Stirling Engine ◽  
Performance Criteria ◽  
Stirling Cycle ◽  
Heat Engines ◽  
Atkinson Cycle

There is immense scope for the development of heat engines that can directly convert solar and biochemical renewable sources of thermal energy to high-grade energy. Regenerative Stirling cycle heat engine with its performance criteria of highest thermal efficiency and high mean effective pressure is theoretically the best engine for small capacity reciprocating heat engine. However, the practical Stirling engine performance is far from the ideal. As an alternative, practical heat engines based on thermodynamic cycles (without regeneration) other than the Stirling cycle have been suggested. This paper deals with a new concept in the design of reciprocating heat engine working on modified Atkinson cycle. In the Atkinson cycle, expansion ratio being higher than compression ratio, the thermal efficiency is better than that of the standard Otto cycle. Heat engine design based on the suggested modified Atkinson cycle can be an alternative to the practical Stirling engine. In the conceptual mechanical design of the engine suggested here, apart from utilizing the principle of Atkinson cycle for achieving higher thermal efficiency, the mechanical configuration of the reciprocating engine ensures a high degree of inertial force balancing. This can result in reduced vibrations in the mountings of the power units.

scholarly journals Utilization of Building Information Modeling for Arranging the Structural Kingposts

Buildings ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 323
Author(s):  
Vachara Peansupap ◽  
Pisal Nov ◽  
Tanit Tongthong
Keyword(s):  
Underground Structure ◽  
Visual Programming ◽  
Information Modeling ◽  
Construction Technology ◽  
Underground Structures ◽  
Building Information Modelling ◽  
Engineering Knowledge ◽  
Building Information ◽  
Rule Based Approach

The kingpost was a vertical element that was used to support the structural strut in the deep excavation. The structural kingpost was commonly arranged by experienced engineers who used two-dimensional construction drawings. Thus, it was still time-consuming and error-prone. Currently, an available construction program has been developed to arrange the structural kingpost by identifying the clash problems in the 3D environment. However, they have a limitation for detecting the clash that was unable to visualize the concurrent clashes between kingpost and many underground structures. Then, the engineer cannot see all the clash incidents with each kingpost and move the kingpost to avoid the clashes successfully. Since the kingpost arrangement was still an inefficient practice that was limited in the visualization aspect, this research used engineering knowledge and advanced construction technology to detect and solve the clashes between kingposts and underground structures. The methodology used engineering knowledge of kingpost arrangement to develop the system modules by using a rule-based approach. Then, these modules were developed into the system by using visual programming of Building Information Modelling (BIM). To test the system, an underground structure from building construction was selected as a case study to apply the developed system. Finally, the finding of this study could overcome human judgment by providing less interaction in the kingpost arrangement and visualization improvement of clash occurrences in the 3D model.

scholarly journals The Effectiveness of Blended Learning in Improving Students’ Workplace Communication Skills: A Case Study on Olive Website Test Result

2020 ◽  
Vol 14 (1) ◽  
pp. 1-13
Author(s):  
Agnes Siwi Purwaning Tyas ◽  
Ahmad Muam ◽  
Yohana Ika Harnita Sari ◽  
Cisya Dewantara
Keyword(s):  
Blended Learning ◽  
Communication Skills ◽  
Test Scores ◽  
Cultural Management ◽  
Engineering Department ◽  
Post Test ◽  
Learning Instruction ◽  
Listening And Speaking ◽  
Academic Year

The research aimed to investigate the effectiveness of using blended-learning instruction in improving students’ communication skills at Sekolah Vokasi Universitas Gadjah Mada. They were required to take the Test of English for Vocational Students (TEVOCS) and it indicated that there was a gap between listening and speaking ability as presented in the test scores. To support the improvement of both skills, blended-learning instruction was designed and carried out in the forms of online listening activities via Online Listening for Individual Practice (OLIVE) website and offline meeting for speaking activities. The research used experimental research, which referred to the results of pre-test and post-test scores of the group. The participants of the research were 275 students from three departments of Sekolah Vokasi Universitas Gadjah Mada; Language, Arts, and Cultural Management department; Engineering department; as well as Economic and Business department academic year 2019/2020. The pre-test and post-test scores show improvement in students’ performance in both skills. The result of the t-test also shows that there is significant improvement after the application of blended-learning instruction.

scholarly journals Analisis Kesulitan Siswa dalam Proses Pemecahan Masalah Geometri Berdasarkan Tahapan Berpikir Van Hiele

2018 ◽  
Vol 6 (2) ◽  
pp. 287-298
Author(s):  
Silfi Zainatu Sholihah ◽  
Ekasatya Aldila Afriansyah
Keyword(s):  
Research Method ◽  
Case Study Research ◽  
Research Subjects ◽  
Qualitative Case Studies ◽  
Van Hiele ◽  
Student Difficulties ◽  
Stage 1 ◽  
Math Problems ◽  
Research Type

AbstrakMatematika memiliki peranan penting dalam kehidupan. Namun, dalam praktik pembelajarannya sebagian siswa masih menganggap matematika sebagai mata pelajaran yang sulit. Bukti-bukti di lapangan menunjukkan bahwa hasil belajar geometri masih rendah. Kesulitan pada materi geometri dapat berdampak pada kesulitan-kesulitan bagian lain dalam materi geometri itu sendiri, karena banyak pokok bahasan dalam geometri yang saling berhubungan. Penelitian ini bertujuan untuk mengetahui faktor penyebab kesulitan siswa dalam proses pemecahan masalah geometri berdasarkan tahapan berpikir Van Hiele serta untuk melihat ketercapaian siswa dalam pemahaman geometri berdasarkan tahapan berpikir geometri Van Hiele. Metode penelitian yang digunakan adalah metode penelitian kualitatif dengan jenis penelitian studi kasus. Subjek penelitian yang diambil sebanyak 6 siswa dari kelas VII C SMP Negeri 6 Garut. Hasil penelitian menunjukkan bahwa ketercapaian siswa pada proses pemecahan masalah geometri berdasarkan tahapan berpikir Van Hiele paling banyak adalah pada tahap 0 (visualisasi). Hal ini ditunjukkan dengan tingginya persentase pencapaian siswa pada tahap visualisasi yaitu sebanyak 96,87 %. Ketercapaian tahapan berpikir Van Hiele yang paling baik dicapai sebesar 3,13% pada tahap 1 (Analisis). Untuk tahap 2 (deduksi informal) dan tahap 3 (deduksi) belum ada siswa yang mampu mencapai tahapan tersebut. Faktor yang menjadi penyebab kesulitan siswa dalam materi segiempat disebabkan karena beberapa hal, yaitu pemahaman mengenai konsep dan sifat-sifat segiempat yang kurang, pemahaman sebelumnya mengenai materi bangun datar segiempat yang masih kurang kuat, kurangnya keterampilan menggunakan ide-ide geometri dalam memecahkan masalah matematika yang berkaitan dengan bangun segiempat, serta kondisi kelas yang kurang kondusif untuk belajar.Kata Kunci: Kesulitan siswa pada geometri, tahapan berpikir Van Hiele, Kualitatif, Studi Kasus.AbstractMathematics has an important role in life. However, in the practice of learning some students still regard mathematics as a difficult subject. The evidence in the field shows that the geometry learning result is still low. Difficulties in geometrical matter can affect the difficulties of other parts of the material itself, since many of the subjects in the geometry are interconnected. This study aims to determine the factors causing student difficulties in the process of solving geometry problems based on the stages of thinking Van Hiele and to see students' achievement in understanding geometry based on the stages of thinking geometry Van Hiele. The research method used is qualitative research method with case study research type. Research subjects taken as many as 6 students from class VII C SMP Negeri 6 Garut. The results showed that students' achievement in the process of solving geometry problems based on the stage of thinking Van Hiele at most is at stage 0 (visualization). This is indicated by the high percentage of student achievement in the visualization stage that is as much as 96.87%. The achievement of the best stage of Van Hiele thinking was achieved at 3.13% in stage 1 (Analysis). For stage 2 (informal deduction) and stage 3 (deduction) no students have been able to reach that stage. Factors that cause student difficulties in rectangular material caused by several things, namely the understanding of the concept and the characteristics of the rectangle is lacking, previous understanding of the material wake rectangular flat that is still less strong, the lack of skills to use geometric ideas in solving math problems Relating to wake up quadrilateral, as well as class conditions that are less conducive to learning.Keyword: Student difficulties on geometry, Van Hiele thinking stages, Qualitative, Case Studies.

scholarly journals INFLUENCE OF MOTIVATION TO RESULT OF COGNITIVE LEARNING IN INTERGRATED NATURAL SCIENCES MODEL TEAM GAMES TOURNAMENT (TGT) ASSITANCE BY YUGIOH CARD

2019 ◽  
Vol 18 (2) ◽  
pp. 20
Author(s):  
Reda Harwinanda
Keyword(s):  
Science Learning ◽  
Cognitive Learning ◽  
Natural Sciences ◽  
Learning Motivation ◽  
Test Results ◽  
Simple Linear Regression ◽  
Team Games ◽  
Post Test ◽  
Positive Effect

The purpose of this study was to examine the effect of motivation on the result cognitive learning of the model TGT assisted YuGiOh Card. The population in this study were students of class VII semester 1 with the number of 16 students at MTs Baitul Amin Bali. The type of research design used was pre-experimental design with a one-shot case study. The study used 2 (two) variables examined in this study, namely motivation and result cognitive learning. The method used in data collection in this research is questionnaire (questionnaire), documentation and test. The collected data were analyzed using simple linear regression. Based on the motivation data obtained using themodel TGT assisted by the YuGiOh card in this study, it shows that students who are in the very good motivation category are 62.5% and good categories are 37.5%. Data on students' resultcognitive learning from post-test results can be categorized very well by 6%, both by 31%, enough by 44% and less by 19%. The influence of motivation on result cognitive learning using the model TGT assisted YuGiOh card is 27.2% while the remaining 72.8% is influenced by learning readiness, social support and learning facilities. The results showed that learning motivation had a positive effect on result cognitive learning in science learning using the model TGT assisted by YuGiOh card.

scholarly journals PENERAPAN DIR FLOORTIME PADA ANAK DENGAN AUTISM SPECTRUM DISORDER UNTUK MENINGKATKAN KEMAMPUAN SOSIAL

Psibernetika ◽  
2019 ◽  
Vol 11 (2) ◽  
Author(s):  
Elita Kirana ◽  
Ediasri T Atmodiwirjo ◽  
Debora Basaria
Keyword(s):  
Autism Spectrum Disorder ◽  
Social Skills ◽  
Individual Differences ◽  
Middle Childhood ◽  
Children With Autism ◽  
Autism Spectrum ◽  
Spectrum Disorder ◽  
Post Test ◽  
Patterns Of Behavior

<p><strong><em>ABSTRACT</em></strong><strong><em>: </em></strong><em>Children with autism have deficit characteristics in social communication and social interaction, as well as restricted and repetitive patterns of behavior, and limited interests or activities. As children grow and engage in a wider environment, this is become a problem because of the lack of social skills on children with autism. The purpose of this research is to improve the social skills of children with autism. There are several methods that can be applied to children with autism to improve their social skills. One of them is the DIR </em>(<em>Developmental, Individual Differences, &amp; Relationship Based</em>) <em>Floortime method. DIR Floortime aims to help children reach the stage of their emotional development through play activities. This type of research is a clinical case study, involving two middle childhood boys that are diagnosed with a mild level of autism. The instruments used in this study are Autism Social Skills Profile and Functional Emotional Assessment Scale. This research involves 20 sessions, conducted in May until June 2018, consisting of 10 sensory sessions and 10  symbolic sessions for each subject. The results of this research show an improvement in social skills in both participants, marked by an increase in the post test scores, but not significantly. Qualitatively, both subject demonstrates an improvement on social skills in their daily behavior after they had participated in the intervention.</em><strong><em></em></strong></p><p><strong><em>Keywords</em></strong><strong>: </strong><em>autism spectrum disorder, middle childhood, </em>DIR <em>Floortime,social skills</em></p><p><strong> </strong></p><p><strong>ABSTRAK</strong><strong>: </strong>Anak autistik memiliki karakteristik kesulitan dalam komunikasi dan interaksi sosial serta adanya yang minat terbatas, perilaku berulang, atau keterikatan dalam minat dan aktivitas. Hal ini menjadi masalah saat anak tumbuh seiring usia dan terlibat dalam lingkungan yang lebih luas karena kurangnya kemampuan sosial pada anak autistik. Penelitian ini bertujuan untuk meningkatkan kemampuan sosial anak autistik. Ada beberapa metode yang dapat diterapkan pada anak autistik untuk meningkatkan kemampuan sosial. Salah satunya adalah metode DIR (<em>Developmental, Individual Differences, &amp; Relationship Based</em>) <em>Floortime</em>. DIR<em> Floortime</em>  bertujuan membantu anak mencapai tahap perkembangan emosionalnya melalui kegiatan bermain. Jenis penelitian ini adalah case study yang melibatkan dua orang partisipan, yaitu anak laki-laki berusia <em>middle childhood</em> dengan autisme <em>level Mild</em>. Instrumen dalam penelitian ini adalah <em>Autism Social Skills Profile dan Functional Emotional Assesment Scale</em>. Penelitian ini berlangsung selama 20 sesi intervensi yang dilaksanakan pada bulan Mei hingga Juni 2018. Sesi intervensi terdiri dari 10 sesi sensori auditori dan 10 sesi simbolik bagi masing-masing subjek. Hasil penelitian menunjukkan adanya peningkatan yang signifikan pada kapasitas emosi, tetapi kemampuan sosial kedua partisipan tidak meningkat secara signifikan. Secara kualitatif, kedua subjek menunjukkan kemampuan sosial yang lebih baik setelah mengikuti sesi intervensi, hal ini tampak dalam perilaku sehari-hari.<strong></strong></p><p><strong>Kata kunci</strong>: autisme<em>, middle childhood, </em>DIR <em>Floortime,</em> kemampuan sosial</p>

scholarly journals Comparing Different Pedagogical Techniques to Teach Spelling at a Saudi High School: A Case Study

2019 ◽  
Vol 7 (1) ◽  
pp. 36
Author(s):  
Saad Althobaiti ◽  
Tariq Elyas
Keyword(s):  
High School ◽  
Saudi Arabia ◽  
High School Students ◽  
Research Method ◽  
Male Students ◽  
School Students ◽  
Repeated Practice ◽  
Post Test ◽  
The Common

<p><em>This study investigates whether teaching spelling to high school students using different techniques, i.e. copy, cover, compare and flip folder, would improve students’ spelling. Additionally, it explores students’ opinions and perceptions towards these techniques. The research conducted in Granada high school in Makkah, Saudi Arabia. Thirty-six male students participated in this study whose levels according to the course book were assumed to be B1 in the Common European Framework of Reference for Languages (CEFR). In this study, a mixed research method was used where data was analyzed quantitatively and qualitatively. The first group was taught using copy cover and compare method (CCC), which emphasizes repeated practice when errors occur in students spelling, whereas the second group was trained using the flip folder technique which is a combination of visual, auditory, and kinesthetic techniques that were believed to enhance memorization. A post-test was utilized immediately after the intervention and the results showed that the CCC group outperformed the Flip Folder group. </em></p>

scholarly journals An Elective Course in Women's Health Issues

2013 ◽  
Vol 4 (3) ◽  
Author(s):  
Natalie A. DiPietro
Keyword(s):  
Women’S Health ◽  
Women's Health ◽  
Community Outreach ◽  
The United States ◽  
Likert Scale ◽  
Health Coverage ◽  
Health Issues ◽  
Post Test ◽  
Elective Course

Purpose: To develop, implement, and evaluate an elective course for the Doctor of Pharmacy (PharmD) curriculum that provides students with a comprehensive overview of women's health across the lifespan and exposes them to social and economic issues that impact women's health. Case Study: At the time of this writing, the class has been delivered 3 times to a total of 56 students. Students read and discussed (both in-class and online) timely articles in women's health issues on topics including sex-based biology; women in clinical trials; maternal and child health; women's health coverage and access to care in the United States; gender and health communication; abuse and the role of healthcare professionals; and international issues in women's health and women's rights. Students completed a pre- and post-test; developed seminar presentations regarding women's health issues; wrote reflective essays about the course; and designed and implemented health promotion projects for National Women's Health Week (NWHW). At the end of the course, the number of correct answers on the post-test significantly improved from the pre-test (p<0.001). Through anonymous course evaluations, students indicated that the assignments fulfilled the learning objectives (mean 4.68 on a 5-point Likert scale) and the exercises were useful in helping their understanding of the material (mean 4.66 on a 5-point Likert scale). Over 500 women from the campus and community participated in the NWHW projects. Implications: An elective course was designed to educate pharmacy students regarding women's health issues and to provide students with an opportunity to perform community outreach.   Type: Case Study

scholarly journals IMPROVING STUDENTS’ READING “DESCRIPTIVE TEXT” USING SMALL GROUP DISCUSSION, A CASE STUDY OF X MIPA-7 CLASS OF 11 SENIOR HIGH SCHOOL SEMARANG IN ACADEMIC YEAR 2018/2019

2019 ◽  
Vol 12 (2) ◽  
pp. 102
Author(s):  
Yongki Arya Permana ◽  
Erna Setyawati ◽  
Maria Yosephine
Keyword(s):  
High School ◽  
Small Group ◽  
Test Data ◽  
Group Discussion ◽  
Senior High School ◽  
Small Group Discussion ◽  
Post Test ◽  
Academic Year

Tujuan dari penelitian ini adalah untuk mendeskripsikan: (1) bagaimana penggunaan Small Group Discussion dapat meningkatkan kemampuan ketrampilan membaca siswa dalam materi descriptive text. (2) Kelebihan menggunakan Small Group Discussion dalam pembelajaran penguasaan ketrampilan membaca. Dalam penelitian tindakan kelas ini dilaksanakan dalam dua siklus pada siswa kelas X MIPA-7 SMA Negeri 11 Semarang. Setiap siklus terdiri dari empat tahapan: perencanaan, pelaksanaan, pengamatan, refleksi. Terdapat dua jenis data: data kualitatif dan data kuantitatif. Data kualitatif diperoleh dengan menggunakan lembar pengamatan, wawancara, dan catatan lapangan. Kemudian, data kuantitatif diperoleh menggunakan tes (pre-test dan post-test). Data kualitatif dianalisis menggunakan 5 tahapan yang disarankan oleh Burns (1999: 157-159) yakni sebagai berikut: menghimpun data, mencatat data, membandingkan data, membangun teori, dan melaporkan hasil penelitian. Data kuantitatif dianalisis menggunakan statistik deskriptif. Hasil penelitian menunjukkan bahwa penggunaan Small Group Discussion dapat meningkatkan kemampuan siswa dalam ketrampilan membaca. Selain itu, Small Group Discussion dapat digunakan untuk mendukung guru dalam pengelolaan kelas. Peneliti juga menemukan kelebihan Small Group Discussion dalam pembelajaran ketrampilan membaca. Small Group Discussion tidak hanya membuat suasana kelas menjadi nyaman dan menarik, akan tetapi juga meningkatkan partisipasi siswa dalam berbagi ide dan bertukar informasi dalam pembelajaran ketrampilan membaca descriptive text.

The Effects of Death Anxiety and Mode of “Case Study” Presentation on Shifts of Attitude toward Euthanasia

1979 ◽  
Vol 9 (3) ◽  
pp. 239-244 ◽  
Author(s):  
Edward J. Hart
Keyword(s):  
Death Anxiety ◽  
Attitude Scale ◽  
Video Tape ◽  
Significant Shift ◽  
Significant Interaction Effect ◽  
Related Data ◽  
Post Test ◽  
Video Group ◽  
Experimental Treatments

The influence of death anxiety and variations in method of “case study” presentation were investigated to determine the effects on shifts of attitude toward euthanasia. College students (N = 18) were randomized to one of two experimental treatments: (I) a video tape presentation of a burn victim who was requesting that treatment be withdrawn, and (II) a written narrative of the same “case study.” All participants were administered the Collett-Lester Death Anxiety Scale [1], and a Likert-type Euthanasia Attitude Scale [2], as a pre-experimental condition approximately four weeks before exposure to the treatments. Following treatment, all participants were readministered the Euthanasia Attitude Scale. Data were analyzed by t-tests for related data to determine pre- to post-test shifts of attitude and by an ANOVA (presentations × death anxiety). There was a significant shift of attitude in the “video” group toward a more supportive posture and a significant shift toward a less supportive posture in the “written” group. There appeared to be significant differences in attitudes toward euthanasia between experimental groups and the data also suggested a significant interaction effect between presentation and death anxiety.

Sign in / Sign up

Export Citation Format

Share Document