scholarly journals A review of hydrogen technologies and engineering solutions for railway vehicle design and operations

2021 ◽  
Vol 29 (3) ◽  
pp. 212-232
Author(s):  
Yan Sun ◽  
M. Anwar ◽  
N. M. S. Hassan ◽  
Maksym Spiryagin ◽  
Colin Cole

AbstractInterest in hydrogen-powered rail vehicles has gradually increased worldwide over recent decades due to the global pressure on reduction in greenhouse gas emissions, technology availability, and multiple options of power supply. In the past, research and development have been primarily focusing on light rail and regional trains, but the interest in hydrogen-powered freight and heavy haul trains is also growing. The review shows that some technical feasibility has been demonstrated from the research and experiments on proof-of-concept designs. Several rail vehicles powered by hydrogen either are currently operating or are the subject of experimental programmes. The paper identifies that fuel cell technology is well developed and has obvious application in providing electrical traction power, while hydrogen combustion in traditional IC engines and gas turbines is not yet well developed. The need for on-board energy storage is discussed along with the benefits of energy management and control systems.

Author(s):  
D K Ware ◽  
R N H Jones

The 1980s saw a resurgence of interest in light rail systems throughout the world and particularly in Great Britain, where they had almost disappeared. Properly planned and executed they can effectively cater for a significant segment of city transport, using nonproprietary technology which is non-polluting and which can make use of a variety of energy sources. This paper outlines some recent trends in the technology of light rail vehicles and control systems, and goes on to describe four new systems of different characteristics or stage of development.


Author(s):  
Jesu´s Otero Yugat ◽  
Igor Alonso Portillo

All railway vehicles running on a track have to overcome a resistance to motion. The resistance to motion is due to mechanical and electrical losses, as well as to aerodynamic drag. In order to evaluate this resistance, two different experimental methodologies can be used. The first one consists on a conventional method which takes into account the energy stored in rotating masses and the equivalent curving and grade resistance. The application of this method is based on a coasting test procedure done on a straight track without slope. The second methodology consists on the experimental acquisition of electrical signals in the traction power line and strain measurements at the traction links of the bogie-truck, with different speeds. The electrical signals allow obtaining the efficiencies of the equipments in the traction power line. Once the different efficiencies of the equipments in the traction power line are known, the power transmitted to each wheel can be determined and consequently the resistance to motion is calculated. This paper summarizes an experimental procedure based on both methodologies. The designed instrumentation uses voltage and current probes for the recording of electrical signals in the traction line, piezorresistive accelerometers in order to obtain the uncompensated and the longitudinal accelerations of the train, extensometric gauges in full bridge configuration for the acquisition of stresses at the traction links, and a gyroscope for the detection of curves along the track. Several tests have been done by means of the described methods in light rail vehicles. Also, the vehicles have been tested in order to evaluate the influence of the air conditioning and air intakes, the circulation in curves and the cooling of traction equipments in the resistance to motion. Through these experimental methods, a useful tool for the prediction and analysis of the resistance to motion is provided. Additionally, the results obtained by means of these methodologies permit to calculate the influence of different running conditions in the resistance to motion.


Author(s):  
Meryanti Napitupulu And Anni Holila Pulungan

This study was conducted as an attempt to discover the effect of applying Demonstration Method on students’ achievement in speaking skill. It was an experimental research. The subject was students of Grade XII, Vocational High School (Sekolah Menengah Kejuruan: SMK), which consisted of 79 students. The research was divided into two groups: experimental and control groups. The instrument used to collect the data was speaking test. To obtain the reliability of the test, the writer applied Kuder Richardson 21 formula. The result of the reliability was 0.7, and it was found that the test was reliable. The data were analyzed by using t-test formula. The analysis showed that the scores of the students in the experimental group were significantly higher than the scores of the students in the control group at the level of significant m = 0.05 with the degree of freedom (df) 77, t-observed value 8.9 > t-table value 1.99. The findings indicate that using Demonstration Method significantly affected the students’ achievement in speaking skill. So, English teachers are suggested to use Demonstration Method in order to improve students’ achievement in speaking skill.


2019 ◽  
Author(s):  
Nur Tsalits Fahman Mughni

Teaching materials by integrating local culture makes easier for students to understand the subject matter in the learning process. The aims of the study is to measure the effectiveness of teaching materials based on local wisdom of agriculture in Binjai in improving the students problem solving abilities. The research method was a quasi experimental which use non equivalent control group in the pretest posttest design. The sample of study were students of Senior High School grade X in Binjai that consisted of experiment group which used teaching materials based on local wisdom of agriculture in Binjai and control group that used student handbooks. Teaching materials are tested by material experts and technology experts to ensure the quality of teaching materials. Data collection was conducted through test. The results showed that the teaching materials based on local wisdom of agriculture in Binjai effective in improving students problem solving abilities in the experimental group students based on the results of N gain value was 0.67 which has medium criteria. It means teaching materials based on agricultural local wisdom of agriculture in Binjai can be used as one of the teaching materials in learning activities.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Paulien Adamse ◽  
Emilie Dagand ◽  
Karen Bohmert-Tatarev ◽  
Daniela Wahler ◽  
Manoela Miranda ◽  
...  

Abstract Background Various databases on genetically modified organisms (GMOs) exist, all with their specific focus to facilitate access to information needed for, e. g., the assistance in risk assessment, the development of detection and identification strategies or inspection and control activities. Each database has its unique approach towards the subject. Often these databases use different terminology to describe the GMOs. For adequate GMO addressing and identification and exchange of GMO-related information it is necessary to use commonly agreed upon concepts and terminology. Result A hierarchically structured controlled vocabulary describing the genetic elements inserted into conventional GMOs, and GMOs developed by the use of gen(om)e-editing is presented: the GMO genetic element thesaurus (GMO-GET). GMO-GET can be used for GMO-related documentation, including GMO-related databases. It has initially been developed on the basis of two GMO databases, i.e. the Biosafety Clearing-House and the EUginius database. Conclusion The use of GMO-GET will enable consistent and compatible information (harmonisation), also allowing an accurate exchange of information between the different data systems and thereby facilitating their interoperability. GMO-GET can also be used to describe genetic elements that are altered in organisms obtained through current targeted genome-editing techniques.


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