scholarly journals Fault diagnosis and maintenance of automobile engine cooling system

2020 ◽  
Vol 4 (1) ◽  
Author(s):  
Chunmei Chen
Keyword(s):  
Fault Diagnosis ◽  
Cooling System ◽  
Reference Value ◽  
Mechanical Equipment ◽  
Automobile Engine ◽  
Engine Cooling ◽  
Economic Level ◽  
Long Time ◽  
Further Development

With the further development of the society, the economic level of Chinese residents is gradually improving. Under such circumstances, the number of automobiles and their usage are increasing as well. As a kind of mechanical equipment, there will be many application faults of the automobile after long-term use. Only by solving the faults can automobiles be restarted and run stably for a long time. Based on this, this paper focuses on automobile maintenance, analyzes the principle of engine cooling system, and studies the diagnosis and maintenance methods of this kind of fault, trying to provide some reference value for the further discussion and research in this field.

scholarly journals Subway Gearbox Fault Diagnosis Algorithm Based on Adaptive Spline Impact Suppression

Entropy ◽  
2021 ◽  
Vol 23 (6) ◽  
pp. 660
Author(s):  
Zhongshuo Hu ◽  
Jianwei Yang ◽  
Dechen Yao ◽  
Jinhai Wang ◽  
Yongliang Bai
Keyword(s):  
Fault Diagnosis ◽  
Spline Interpolation ◽  
Reference Value ◽  
High Amplitude ◽  
Engineering Practice ◽  
Negative Effects ◽  
Short Term ◽  
Time Domain Signal ◽  
Gearbox Vibration ◽  
Long Time

In the signal processing of real subway vehicles, impacts between wheelsets and rail joint gaps have significant negative effects on the spectrum. This introduces great difficulties for the fault diagnosis of gearboxes. To solve this problem, this paper proposes an adaptive time-domain signal segmentation method that envelopes the original signal using a cubic spline interpolation. The peak values of the rail joint gap impacts are extracted to realize the adaptive segmentation of gearbox fault signals when the vehicle was moving at a uniform speed. A long-time and unsteady signal affected by wheel–rail impacts is segmented into multiple short-term, steady-state signals, which can suppress the high amplitude of the shock response signal. Finally, on this basis, multiple short-term sample signals are analyzed by time- and frequency-domain analyses and compared with the nonfaulty results. The results showed that the method can efficiently suppress the high-amplitude components of subway gearbox vibration signals and effectively extract the characteristics of weak faults due to uniform wear of the gearbox in the time and frequency domains. This provides reference value for the gearbox fault diagnosis in engineering practice.

scholarly journals Domain Adaptation Network with Double Adversarial Mechanism for Intelligent Fault Diagnosis

2021 ◽  
Vol 11 (17) ◽  
pp. 7983
Author(s):  
Kun Xu ◽  
Shunming Li ◽  
Ranran Li ◽  
Jiantao Lu ◽  
Xianglian Li ◽  
...  
Keyword(s):  
Fault Diagnosis ◽  
Domain Adaptation ◽  
Wasserstein Distance ◽  
Diagnostic Methods ◽  
Mechanical Equipment ◽  
Intelligent Fault Diagnosis ◽  
Sample Distribution ◽  
Feature Extractor ◽  
Long Time ◽  
Diagnosis Method

Due to the mechanical equipment working under variable speed and load for a long time, the distribution of samples is different (domain shift). The general intelligent fault diagnosis method has a good diagnostic effect only on samples with the same sample distribution, but cannot correctly predict the faults of samples with domain shift in a real situation. To settle this problem, a new intelligent fault diagnosis method, domain adaptation network with double adversarial mechanism (DAN-DAM), is proposed. The DAN-DAM model is mainly composed of a feature extractor, two label classifiers and a domain discriminator. The feature extractor and the two label classifiers form the first adversarial mechanism to achieve class-level alignment. Moreover, the discrepancy between the two classifiers is measured by Wasserstein distance. Meanwhile, the feature extractor and the domain discriminator form the second adversarial mechanism to realize domain-level alignment. In addition, maximum mean discrepancy (MMD) is used to reduce the distance between the extracted features of two domains. The DAN-DAM model is verified by multiple transfer experiments on some datasets. According to the transfer experiment results, the DAN-DAM model has a good diagnosis effect for the domain shift samples. Moreover, the diagnostic accuracy is generally higher than other mainstream diagnostic methods.

Long Term Measuring of Expansions and Contractions of Pre-Stressed Concrete Bridge Structure

2016 ◽  
Vol 714 ◽  
pp. 201-206
Author(s):  
Miroslav Vokáč ◽  
Tomáš Bittner ◽  
Petr Bouška ◽  
Petr Klimeš ◽  
Roman Šafář
Keyword(s):  
Statistical Approach ◽  
Standard Procedure ◽  
Bridge Structure ◽  
Railway Bridge ◽  
Minimal Difference ◽  
Long Time ◽  
Standard Value ◽  
Standard Values ◽  
Further Development

The presented paper considers approx. 5 years measurement on concrete railway bridge. The span is 39.875 + 34.877 + 37.000 + 9 x 31.500 m. The total length of the bridge is 443 m. Structure possesses typical three-box cross section. Monitoring was focused on temperature of concrete, temperature of atmosphere in the shade and mainly on measurement of movements of several bearings. Because the monitoring period of bridge structure was approx. 5 year, the probability p = 0.2 (5 years returning period) was chosen in order to compare measured data with standard values according to EN 1991-1-5. Of course, the standard value was assumed without any safety factor for this purpose. The maximal difference of measured and standard values was only 25 mm. This was achieved on the pillar where measured value of displacement range was 135 mm, standard value 160 mm and the dilatation length was 332 m. On the other hand, the minimal difference was only 3 mm on the pillar where measured value was 33 mm, standard value 36 mm and the dilatation length was 75 m. If the approx. 5 years measurement is compared with theoretical value of 5 years return period, the standard procedure cannot be classified as very conservative. It was shown that the long-time measurement is very important for the further development and improvement of the Eurocodes as well as statistical approach, i.e., returning time which shall be taken into account.

Cooling performance and power consumption analysis of automobile engine cooling system

2021 ◽  
pp. 1-18
Author(s):  
Yong Wang ◽  
Linglin Jiang ◽  
Houlin Liu ◽  
Jun Yan ◽  
Marko Hočevar ◽  
...  
Keyword(s):  
Power Consumption ◽  
Cooling System ◽  
Automobile Engine ◽  
Cooling Performance ◽  
Engine Cooling

scholarly journals CONFLICTIZATION OF UKRAINIAN ETHNOCULTURAL SPACE AS THE OBJECT OF UKRAINIAN STUDIES

2019 ◽  
pp. 28-34
Author(s):  
Yuriy Fihurnyi
Keyword(s):  
Historical Development ◽  
Nation Building ◽  
Ethnic Community ◽  
Christian Faith ◽  
Self Organization ◽  
Cultural Processes ◽  
Long Time ◽  
The Common ◽  
Further Development

The article deals with the essence of Ukrainian ethnic, national and ethnocultural processes and their influence on the development of the Ukrainian ethnocultural space as an object of Ukrainian studies. Ethnic processes have been found to be sequential changes that have occurred and will occur with the Ukrainian people throughout their development and existence as a self-sufficient ethnic community, and are directly related to the ethnogenesis of Ukrainians. It is proved that nation-building processes are complex transformations that occur both in a regular order (evolutionary) and abrupt (revolutionary) and contribute to the formation of a nation, the highest form of political structuring of the ethnic group and its further development and self-organization, which eventually lead to political emergence. nation, and the creation of Ukrainian civil society. It is shown, that the Ukrainian ethno-cultural processes is a process of a long-term historical development, in which Ukrainians created on the territories of their existence an ethno-cultural space based on the common origin and territories of Ukrainians, the existence of traditional Ukrainian culture, the intriduction of the Christian faith. It was pointed out that the Ukrainian ethnocultural space includes a peculiar and unique complex of material and spiritual culture of the Ukrainian people created during a long time, and acquired originality and perfection. Eight “conflicting points” in Ukrainian ethnocultural development have been determined. The synergistic interaction of ethnic, state-forming, nation-forming and ethno-cultural processes contributed to the long-time consistent development of the Ukrainians from a small ethnic community lived in the Middle Dnieper as their core trerritiry to the modern nation whose representatves are living on different continents.

scholarly journals The significance of the tourist destination of Zlatibor spatial planning

2013 ◽  
Vol 93 (2) ◽  
pp. 91-112
Author(s):  
Ana Jovicic ◽  
Dejan Beric ◽  
Marko Petrovic ◽  
Snjezana Gagic
Keyword(s):  
Spatial Planning ◽  
National Level ◽  
Basic Function ◽  
Aesthetic Value ◽  
Tourist Destination ◽  
Long Time ◽  
And Control ◽  
Further Development

The territory of Zlatibor is known as a region of exquisite beauty, rich in natural and anthropogenic values, and as such it is a significant tourist destination. The tourism on Zlatibor started developing a long time ago, however, recently there has formed a type of settlement with tourism as its basic function, with no adequate planned development and control, which deviates from the natural and aesthetic environment, disturbing the rare and autochthonous quality of the territory. Zlatibor?s beauty has been disturbed with unplanned construction and the development of tourism which is not sustainable in the long-term. The aim of this paper is to point out to the significance of spatial planning for further development of tourism on this mountain and give suggestions on further development which would neutralise, revitalise and improve the already degraded territory. Only by managing the territory of Zlatibor properly, as a resource for tourism, will its economic, ecologic and aesthetic value increase, which will ensure a long term benefit on a local, regional and national level.

Enhancing the power generation of Rhodopseudomonas palustris-based MFC

2020 ◽  
Vol 64 (1-4) ◽  
pp. 1261-1268
Author(s):  
Shu Otani ◽  
Dang-Trang Nguyen ◽  
Kozo Taguchi
Keyword(s):  
Activated Carbon ◽  
Rhodopseudomonas Palustris ◽  
Ozone Treatment ◽  
Maximum Power Density ◽  
On Demand ◽  
Long Time ◽  
Dry Conditions ◽  
Carbon Sheet ◽  
Uv Ozone

In this study, a portable and disposable paper-based microbial fuel cell (MFC) was fabricated. The MFC was powered by Rhodopseudomonas palustris bacteria (R. palustris). An activated carbon sheet-based anode pre-loaded organic matter (starch) and R. palustris was used. By using starch in the anode, R. palustris-loaded on the anode could be preserved for a long time in dry conditions. The MFC could generate electricity on-demand activated by adding water to the anode. The activated carbon sheet anode was treated by UV-ozone treatment to remove impurities and to improve its hydrophilicity before being loaded with R. palustris. The developed MFC could generate the maximum power density of 0.9 μW/cm2 and could be preserved for long-term usage with little performance degradation (10% after four weeks).

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