EuroBrake 2021 Technical Programme最新文献

{"title":"IT-Dimensions of Swarm-based Measurement of Particulate Matter","authors":"Guido Lehne-Wandrey, Jan Malte Sandgaard, G. Ostermeyer","doi":"10.46720/6231369eb2021-stp-004","DOIUrl":"https://doi.org/10.46720/6231369eb2021-stp-004","url":null,"abstract":"Observation and assessment of air quality is not only a growing field of scientific research, but is also increasingly becoming the focus of public interest. Political interventions have succeeded in improving air quality not only in Germany, but also in many other countries, since the turn of the millennium. For this purpose, stricter requirements have been issued on limit values for household and traffic-related emissions. Due to technological progress, exhaust emissions could be reduced. As a result, other emission sources are now coming to the fore. These include particulate emissions from tire abrasion and vehicle brakes. The monitoring of the limit values for particulate matter pollution is carried out throughout Europe by means of scattered, highly precise but also very expensive measuring stations. Furthermore, these measuring stations generally only provide hourly to daily average values. Due to the low spatial and temporal resolution, only one statement about the success of all measures can be made. Individual causes and actions cannot be considered separately. For the investigation of individual events, for example braking and starting before a traffic light, a finer temporal and spatial resolution of the fine dust measurement is required. In this work, a consideration of necessary information-technical measures for the creation of a swarm structure for the measurement of fine dust emissions takes place. This enables the finer resolution of individual emission events as required above. Furthermore, it offers the possibility to investigate dynamics and effects which could not be detected by single sensors only.","PeriodicalId":315146,"journal":{"name":"EuroBrake 2021 Technical Programme","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131381769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Benchmarking the Adaptive Wheel Slide Protection","authors":"L. Imbert, Matteo Frea","doi":"10.46720/6676035eb2021-stp-003","DOIUrl":"https://doi.org/10.46720/6676035eb2021-stp-003","url":null,"abstract":"With the ever-increasing railway traffic on existing lines railway operators are requesting means to increase line capacity, operational resiliency and lower Life Cycle Costs. WSP systems integrated in railway vehicles can address the three aspects. Indeed, a shorter braking distance in low wheel/rail adhesion conditions can increase the line capacity by allowing the vehicles to safely travel closer to each other. Furthermore, WSP systems with better performing algorithms in very and extremely low wheel/rail adhesion conditions would lead to less wheel locks and lower wheel slide velocities diminishing the number of wheel flats and overall wheel damage, thereby reducing the LCC. The increased performance in these conditions would also lead to an increased resiliency to environmental conditions. As a follow-up to the work presented in the paper entitled “ADAPTIVE WHEEL SLIDE PROTECTION ALGORITHMS” - EB2019-IBC-010, a two-point investigation is led to evaluate how the A-WSP addresses the railway operators needs. The first investigation will quantify the differences in terms of braking distance and air consumption between a WSP device incorporating a traditional WSP algorithm and a WSP device incorporating an adaptive WSP algorithm. The second investigation will quantify differences in terms of wheel flats and wheel damage between a WSP device incorporating a traditional WSP algorithm and a WSP device using an adaptive WSP algorithm, The quantification of both investigations will be done at least according to EN15595:2018 criteria and could be extended if these do not provide a holistic view of the differences. The quantification will be based on the analysis of test results from a hardware in the loop test bench and on test results from the Multi-axle Roller Rig present in Wabtec’s laboratory.In order to produce a realistic output, the hardware in the loop test bench and the Multi-axle Roller Rig will be configured according to the characteristics of an existing vehicle and subjected to a real mission profile including the most critical situation identified by railway operators.","PeriodicalId":315146,"journal":{"name":"EuroBrake 2021 Technical Programme","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115669111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Brake Noise Detection Using Artificial Intelligence","authors":"Fabio Squadrani, Danilo Mendes Pedroso, Kenneth Mendoza, Juan J. García Bonito, Juan Pablo Barles, Antonio Rubio","doi":"10.46720/5213812eb2021-stp-015","DOIUrl":"https://doi.org/10.46720/5213812eb2021-stp-015","url":null,"abstract":"Research and/or Engineering Questions/Objective: The availability of big sets of data coming from brake durability tests paves the way for making predictions and decisions related to the noise coming from brakes. In this paper, the workflow for detecting brake squeal and all its main characteristics is presented. Methodology: Initially, a uniform set of data is generated, having a repetitive structure and format. This set of data will be used to train the machine learning algorithm. From the raw data coming from the vehicle data acquisition system, a spectrogram is mathematically generated, to graphically associate sound pressure level and noise frequency within the time domain. These spectrograms will be used to train the machine learning algorithm, which will be recognizing brake noise using the spectrogram images. The final objective is to detect squeal and to identify the frequency, sound pressure level, and subjective rating as well. Results: Once the algorithm is trained with thousands of brake noise events coming from real-life brake durability, brake noise is detected with a very high level of confidence. Currently, brake squeal is the noise being identified during this first phase of the project and is identified with a proper level of confidence, including frequency and SPL. In the second phase of the project, the algorithm is also being evolved to associate a rating to the squeal noise event detected. The algorithm is capable to predict the subjective rating provided by a professional driver during standard driving or during specific noise research maneuvers. Limitations of this study: The real-time detection is currently under investigation and could affect the resolution of the spectrogram to be used to train the algorithm and to detect the brake noise. However, the current level of the study does not currently show any predictable problem that could arise when the machine learning algorithm is embedded within a real-time system. Other brake noises should also be identified, even if less amount of data is available when compared with brake squeal. Conclusion: The study shows an alternative method for automatic noise detection and shows the possibility of automatically rating the brake noise. Real-time detection is also investigated and the results of its initial integration within embedded systems is shown.","PeriodicalId":315146,"journal":{"name":"EuroBrake 2021 Technical Programme","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126458229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acoustic Certification of New Composite Brake Blocks","authors":"S. Doersch, M. Starnberg, H. Brick","doi":"10.46720/1766833eb2021-stp-022","DOIUrl":"https://doi.org/10.46720/1766833eb2021-stp-022","url":null,"abstract":"In the latest amendment to the TSI Noise, the Commission Implementing Regulation (EU) 2019/774 from year 2019 (TSI NOI EU 2019/774, 2019), the term “quieter brake blocks” was introduced. The purpose was to distinguish between brake blocks that cause a high rolling noise level by roughening the surface of the wheels and quieter brake blocks with acoustic properties that better correspond to the pass-by noise limit for freight wagons. However, it has remained an open point which methods and procedures should be used for the assessment of the acoustic properties of new brake blocks. This open point shall be closed in the new revision of the TSI Noise, which will become effective in year 2022. It requires a new acoustic certification procedure for brake blocks to be developed. A new procedure for the acoustic certification of new brake blocks should be reliable, easy to use and less expensive in terms of time and costs than full scale pass-by noise measurements in field. These conditions could be fulfilled by a certification procedure based on the wheel roughness level caused by the specific brake block. The relationship to the TSI-noise limit value can be established by defining reference values for the rail roughness and transfer function according to the well-established rolling noise model. Besides the certification procedure, a practical method should be defined how to generate and assess the wheel roughness that is characteristic for a specific brake block product. This project is financed by the German Centre for Rail Traffic Research in cooperation with the Federal Railway Authority and executed by DB Systemtechnik GmbH. The objective of the presentation is to introduce the research project “Acoustic Certification of New Composite Brake Blocks”. This presentation summarizes the project work so far and gives explanations and background knowledge to the development of the methods as well as to railway noise. A calculation example is given to comprehensibly demonstrate the proposed procedure. At the time of the EuroBrake conference the project is still ongoing, and the final results cannot yet be presented. The focus for the discussions is to put on the practicability of the methods and the needs of the user regarding for instance documentation, required efforts or material and qualification.","PeriodicalId":315146,"journal":{"name":"EuroBrake 2021 Technical Programme","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131509683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Automatic Pad Thickness Variation Tester","authors":"Seung Bok Kim","doi":"10.46720/1374610eb2021-stp-017","DOIUrl":"https://doi.org/10.46720/1374610eb2021-stp-017","url":null,"abstract":"Pad thickness variation measurement is done by hand manually so far and the measurement area is limited like around 10 points depend on the pad size due to the complicate marking and measuring method . With the circumstance , reliability and accuracy could not be guaranteed against other fields are automated. Our engineering team is developing Pad Thickness Automatic Measuring System ( PTAMS ). PTAMS is consist of Universal concept of pad grip and feeding module that adapts various kind of shape and size of pad and feed to the sensing area. Non-contact type of displacement sensors scan scan full surface of both friction and back plate side at the same time to measure thickness distribution . The sensors are mounted on the air bearing slide that enable vibration free movement along with fine flatness that maintain stable accuracy to be long lasted. PC based control and data acquisition system enable us to compose scanning widths and mapping conditions for the full surface so that we can investigate full or certain area of wear out ratio or trend freely . Versatile analyzing software offers historical abrasion trend and 3D image of profile that helps investigating geometrical variation of friction part and back plate etc. PTMAS serves hand free , scrip free and enhance accuracy , reliability and investigation","PeriodicalId":315146,"journal":{"name":"EuroBrake 2021 Technical Programme","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134071755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Variable Velocity Tribotester","authors":"G. Ostermeyer, A. Vogel, Jacek Kijanski, Malte Sandgaard, Guido Lehne-Wandrey","doi":"10.46720/1951153eb2021-stp-005","DOIUrl":"https://doi.org/10.46720/1951153eb2021-stp-005","url":null,"abstract":"Friction tests under controlled conditions are crucial for the understanding of the boundary layer dynamics in technical brake systems. The dynamics of the friction interface characterize the braking performance, which has to be evaluated and monitored in the early stages and throughout the development process of new friction materials. For this purpose, detailed insights into the friction behavior is obtained by high precision tribotesters under laboratory conditions. Especially in the low sliding speed range, specialized machines such as the Variable Velocity Tribotester (VVT) make it possible to mimic real world phenomena under controlled conditions, e.g. creep groan or COF in low temperatures. The VVT is modularly designed with two linear stages to move the test specimen and a highly capable servor motor for the rotation of the brake disc. A rotational disk speed of up to 400 rpm is reached with a resolution of 25 bit and a 1:10 gearbox. The normal load can reach up to 300 N (approx. 45 bar brake line pressure) by utilizing a leaf spring load unit. A 3-axis piezoelectric force sensor directly at the test specimen measures the applied and resulting forces.In addition to the friction testing, it is possible to automatically move the specimen to a high precision 3D laser scanning device with stripe light projection and to record height information and pictures of the friction surface. For measurements below room temperature, the VVT is located in an insulated chamber and equipped with two cooling aggregates","PeriodicalId":315146,"journal":{"name":"EuroBrake 2021 Technical Programme","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123231194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Universal Brake Disc Analysis with New High-speed Thermographic Systems for Automated Test Bench Solutions","authors":"Steffen Sturm","doi":"10.46720/7425243eb2021-stp-009","DOIUrl":"https://doi.org/10.46720/7425243eb2021-stp-009","url":null,"abstract":"The increasing demands for quality and lifetime of wearing parts and new materials and designs in braking systems require profound investigations on the relevant assemblies and components. For the investigation of the thermal behaviour during load tests of brake discs InfraTec has developed with permanent new input and further requests since 15 years a thermography based test bench solution Thermal Rotate Check (TRC). Based on the latest technology of cooled highspeed photon detectors the brake disc to be measured is scanned at frame rates up to some kilohertz and speeds up to 400 km/h and can be analysed today in a detail which was never before reached. The data acquisition starts automatically and triggered by the system in interaction with the interface for process signals. For display, archiving and further examination the data are transformed in circular ring or flat projection format and interacts with the master dynamometer stand (test bench). The real time measurement with TRC allows a contactless and fully synchronized raw data acquisition of thermal state and energy distribution of brake discs during different test scenarios. All thermal active areas, abnormal behaviour and hot spots for both sides of brake disc are automatically displayed and recorded. So the complete thermal braking process and interaction between brake disc and brake pad can be analyzed and documented in a way and detail which could not made with any other measurement system in the past. The presentation gives an overview of latest hardware and software developments with advantages and samples for this automatic thermographic test solution and interaction with different dynamometers stands.","PeriodicalId":315146,"journal":{"name":"EuroBrake 2021 Technical Programme","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130132229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Test Bench Brake Calliper with Maximum Power Range","authors":"Armin Diller, J. Gaßner","doi":"10.46720/5834340eb2021-stp-018","DOIUrl":"https://doi.org/10.46720/5834340eb2021-stp-018","url":null,"abstract":"RENK Test System is one of the world´s leading providers of customized test systems used in development, production and quality assurance. Based on its many years of experience, RTS develops innovative test rigs for nearly every area of application in drive technology. A very interesting area are brake dynamometers for the development of rail friction brake systems. When designing a brake test stand, it is advantageous if it is suitable for testing various brake systems from a wide variety of vehicle classes. For this reason, RENK has developed a special brake calliper for testing disc brake pads, which is superior to standard brake callipers in many areas:- The interface of this test bench brake calliper allows the assembly of all relevant brake pads for railway disc brakes.- The performance range of the test bench brake calliper covers the maximum requirements of all possible brake pads (highest vehicle mass - highest vehicle speed) and allows targeted overloads for special tests. Depending on the test requirements, this test bench brake calliper works with pneumatic brake force support. The direct force measurement necessary for the certification of the brake system test rig according to UIC 548, which has to be retrofitted at great expense for standard brake callipers for the test rig application, is already available and can even be supplemented by further sensors.- Despite this versatility, the test bench brake calliper that has been developed is more wear-resistant than standard brake callipers. A first brake calliper was successfully tested at RENK over a period of approx. 2 months this year and is to be handed over to a customer in 2021. A second brake calliper will be subjected to further tests in the spring of 2021 in Augsburg. The proposed lecture is intended to provide an overview of the development activities that have been carried out and are still planned: Why did RENK decide to develop a special brake calliper for test bench operation? What are the weak points when using a standard brake calliper? What development goals have been set for this test bench brake calliper? Which performance range should this development cover? What experiences have been gained so far from the practical use of the test bench brake calliper? Which optimization measures have already been carried out? How does it behave in contrast to standard brake callipers? What remaining work still needs to be done in the development of this special brake calliper?","PeriodicalId":315146,"journal":{"name":"EuroBrake 2021 Technical Programme","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128989079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Psychoacoustic Characteristics of Non-Linear Automotive Disk Brake Creep Groan: a Method Based on Accelerometer Data","authors":"Severin Huemer-Kals, Máté Tóth, Dominik Angerer, Manuel Pürscher, F. Coren, J. Prezelj, M. Zacharczuk","doi":"10.46720/8232461eb2021-stp-011","DOIUrl":"https://doi.org/10.46720/8232461eb2021-stp-011","url":null,"abstract":"The nature of friction within a vehicle’s disk brake system can cause a wide range of different noise phenomena. Especially high-frequency brake squeal was examined during the last decades. Numerous publications treat squeal phenomenology and its mitigation. Increasing shares of electrified powertrains, automatic driving functions such as park assists and further increasing quality demands have now shifted the research interest more and more towards low-frequency phenomena. One of these low-frequency phenomena is creep groan. Defined by its main frequency below 200 Hz, creep groan is characterized by a highly non-linear behavior: Global stick-slip transitions in the disk/pad contacts repeatedly excite the whole brake and axle system. Different bifurcations or even chaotic behavior occur. To ensure good creep groan behavior, defined assessment procedures and rating criteria are necessary. Currently, the German Association of the Automotive Industry recommends a combined rating via the subjective perception of trained test drivers and the objective, A-weighted sound pressure level. This practice could be improved with a more sophisticated objective rating: By considering the human perception, objective and subjective ratings would correlate even better. One possible approach towards an enhanced objective creep groan rating could therefore use psychoacoustic metrics. In 2009, this idea was formulated for the psychoacoustic loudness and the tonality of creep groan by Abdelhamid and Bray. The present work seizes this suggestion and provides additional psychoacoustic evaluations of full-vehicle creep groan signals. Based on measured accelerometer signals, a novel procedure for the psychoacoustic evaluation of structure-borne noise was applied: Optimized FIR filter transfer functions were used to compute equivalent sound pressure signals from the accelerometer data, with the equivalent signals resembling the measured signals but lacking unwanted noise. Both the measured and the simulated signal were then evaluated and compared regarding their psychoacoustic behavior. Results reveal the value of the equivalent sound pressure signal: Whereas loudness and sharpness were found very similar and tonality rather arbitrary for both measured and equivalent sound pressure signal, roughness and fluctuation strength showed strong differences between the signals: Here, only the accelerometer-based, equivalent sound pressure provided easily interpretable characteristics. The proposed method also compared psychoacoustic characteristics for different creep groan bifurcations. Possible applications comprise an enhanced objective rating of low-frequency noise phenomena, the detection and classification of creep groan bifurcations, or the possibility to estimate creep groan cabin noise based on simulative results during early development stages. Therefore, this study provides another step towards silent automotive brake technology.","PeriodicalId":315146,"journal":{"name":"EuroBrake 2021 Technical Programme","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116935646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of System Boundary Condition on the NVH Behaviour of Bogie Brake Simulation","authors":"G. Ostermeyer, Andreas Krumm, F. Schiefer, Sebastian Montua","doi":"10.46720/1735035eb2021-stp-010","DOIUrl":"https://doi.org/10.46720/1735035eb2021-stp-010","url":null,"abstract":"As in many other industries, weight reduction also plays an important role in the product development of train manufacturers and suppliers. Due to the ongoing weight reduction of the bogie and the components, they are becoming increasingly sensitive to NVH phenomena. A particularly critical component here is the brake, as the non-linear friction contact between the brake pad and the disc makes it predestined for self-excited vibration phenomena and thus for NVH phenomena. In this paper, vibration phenomena known from field tests will be investigated with respect to their systemic influence. Three different models of bogie brakes are considered to perform a complex eigenvalue analysis (CEA), where the level of detail of the model and the boundary conditions are different. The first model is a very detailed model of the brake with highly simplified boundary conditions. The second model is an extension of the first model where an additional wheel axle has been added. By including the axle, the brake disc gets additional degrees of freedom, where additional vibrations can be considered. The third model includes an entire wheel set with brake units. This model has been simplified to investigate phenomenologically vibrations of the entire wheelset and to consider systemic influences. With these three models an evaluation of the influence of the boundary conditions on the NVH behaviour should be carried out. For all modal analyses, the real part of the eigenvalue is used as an essential evaluation criterion and is applied to evaluate the impact of the boundary conditions on the observed vibration phenomena or the stability of the eigenfrequencies. Thereby a sensitivity analysis of the individual boundary conditions with respect to the eigenfrequencies is also a target","PeriodicalId":315146,"journal":{"name":"EuroBrake 2021 Technical Programme","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132507524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}