@misc{13433, abstract = {{The use of lubricants on electrical connector contacts is essential for certain applications in order to reduce mating forces, minimize wear, and mitigate fretting corrosion. However, increasing performance requirements (e.g., operation at elevated temperatures) and regulatory restrictions are prompting a reassessment of lubricant selection. In this study, the influence of three lubricants (one oil and two greases), operating temperature (room temperature and 130°C), and applied volume (low, medium and high volume) on electrical contact resistance (ECR) and coefficient of friction (CoF) is investigated by means of fretting wear tests on silver-plated contacts. The results show that unlubricated silver contacts exhibit a longer stable phase at 130 °C than at room temperature. For lubricated contacts, service life is influenced by both temperature and lubricant volume. Certain lubricants demonstrate earlier fail at room temperature than at elevated temperatures. The findings highlight the importance of careful selection and optimization of lubricants for electrical connectors under varying environmental conditions.}}, author = {{Blauth, Michael and Tülling, Sören and Song, Jian}}, booktitle = {{Proceedings of the 70th IEEE Holm Conference on Electrical Contacts (HLM)}}, isbn = {{979-8-3315-5997-7}}, issn = {{2158-9992}}, keywords = {{Connectors, Resistance, Silver, Lubricants, Contacts, Oils, Friction, Corrosion, Optimization}}, location = {{San Antonio, TX, USA }}, publisher = {{IEEE}}, title = {{{Effect of Operating Temperature and Application Quantity of Lubricants on the Fretting Behavior of Silver Plated Electrical Contacts}}}, doi = {{10.1109/hlm51652.2025.11278329}}, year = {{2025}}, } @misc{11360, abstract = {{The state of health and lifetime estimation process of electrical connectors via lifetime tests is a time and labor intensive process. In our previous work, a correlation between the contact resistance developments in the early stages of lifetime tests of electrical connectors with the final results was established using a data driven statistical process based on probability distribution. Also, state of health indicators for prognosis of lifetime were introduced. In this work, the state of health indicators have been optimized. The sensitivity analysis is performed with regards to the selection of the appropriate amount of test data based on test duration for the reliable prognosis of the state of health and the characteristic lifetime. Through this the possibility of further reduction of test duration required for the reliable prognosis of state of health is investigated. Based on the results of analysis, a guideline for the determination of the duration of lifetime tests which lead to a reliable prediction of lifetime of connectors can be provided. Also, an assessment of the state of art in the prognosis of the lifetime of electrical connectors has been presented.}}, author = {{Song, Jian and Shukla, Abhay Rammurti and Probst, Roman}}, booktitle = {{2023 IEEE 68th Holm Conference on Electrical Contacts (HOLM)}}, isbn = {{979‐8‐3503‐4244‐4}}, issn = {{2158‐9992}}, keywords = {{accelerated life testing, test duration, contact resistance, statistical model, connector reliability}}, location = {{Seattle}}, pages = {{200--208}}, publisher = {{IEEE}}, title = {{{Advances in Evaluation of State of Health of Electrical Connectors}}}, doi = {{10.1109/holm56075.2023.10352279}}, year = {{2023}}, } @misc{9210, abstract = {{In order to guarantee long lifetime and high performance of electrical contacts, a plating is usually applied on the base material. Silver is a promising plating material because of a good balance between performance and costs. The conventional silver plating is soft; therefore, a thick silver plating should be used to prevent the wear through during the operation. In order to enhance the wear resistance and prolong the lifetime of the silver plating, silver platings are modified by co-depositing nanoparticles with a core/shell structure into the silver matrix. A novel method to prepare the Ag (shell)@Al 2 O 3 (core) nanoparticles by galvanic process is introduced in this paper. The influence of fabrication parameters in the galvanic process such as the concentration of silver nitrate solution and the plating voltage on the silver content in the Ag@Al 2 O 3 nanoparticles is investigated. Afterwards, different concentrations of core/shell nanoparticles are co-deposited into the silver plating to study the effect of nanoparticles on the microhardness, microstructure and the lifetime of the silver plating. As a result, the microhardness and the lifetime of the silver plating are significantly improved and a favorable nanoparticle concentration exists for the longest lifetime. Moreover, the mechanism of the lifetime improvement is determined.}}, author = {{Yuan, Haomiao and Probst, Roman and Song, Jian}}, booktitle = {{Electrical contacts - 2022 : proceedings of the Sixty-Seventh IEEE Holm Conference on Electrical Contacts}}, isbn = {{978-1-6654-5966-2}}, issn = {{978-1-6654-5965-5}}, keywords = {{Nanoparticles, Resistance, Fabrication, Silver, Costs, Contacts, Voltage}}, location = {{ Tampa, FL, USA}}, pages = {{166 -- 173}}, publisher = {{IEEE}}, title = {{{Influence of Core/Shell Nanoparticles on the Fretting Behavior of Electrical Contacts}}}, doi = {{10.1109/HLM54538.2022.9969773}}, year = {{2022}}, } @misc{9211, abstract = {{Lifetime tests of connectors are time consuming and labor intensive. Our study reveals a strong correlation between the statistical characteristics of contact resistance development in the early stages of lifetime tests and the final results of the tests. This correlation enables a further time lapse of lifetime tests and the prediction of the state of the health of connectors which can be utilized in the development of diagnostic strategy in sophisticated networks with very high number of connectors as well as in a quick classification of connectors with respect to their design features. Methods of statistical evaluation are introduced and the sensitivity analyses of different characteristics for the state of health of connectors are conducted.}}, author = {{Song, Jian and Shukla, Abhay Rammurti and Probst, Roman}}, booktitle = {{Electrical contacts - 2022 : proceedings of the Sixty-Seventh IEEE Holm Conference on Electrical Contacts}}, isbn = {{978-1-6654-5966-2}}, issn = {{2158-9992}}, keywords = {{Connectors, Correlation, Sensitivity analysis, Contact resistance, Lifetime estimation, Reliability, Electrical resistance measurement}}, location = {{Tampa, FL, USA}}, pages = {{272 -- 278}}, publisher = {{IEEE}}, title = {{{State of Health of Connectors – Early Indicators}}}, doi = {{10.1109/HLM54538.2022.9969839}}, year = {{2022}}, } @misc{9213, abstract = {{The function and reliability of electrical connectors in automotive applications is crucial for vehicle safety, especially with regard to E-mobility and autonomous driving. For this reason, electrical connectors are being developed for long-term use applications. However, a small amount of function failures are still being observed in long-term use field vehicles. In this study all electrical connectors of five long-term driven vehicles from various car manufacturers are disassembled and analyzed. The same analysis procedure is followed for every vehicle and the electrical resistance of the connectors is measured to determine electrical failures. The contacts of failed connectors are further analyzed using optical microscopy, XRF spectroscopy, EDS and detailed contact resistance mapping. By comparing the connectors with electrical failures to the same types of connectors with a proper electrical resistance, failure mechanisms can be detected and analyzed. The frequency of various failure mechanisms is statistically evaluated. The results of the analysis provide valuable indications with respect to improvement of the reliability of connectors.}}, author = {{Hilmert, Dirk and Yuan, Haomiao and Song, Jian}}, booktitle = {{Electrical contacts - 2022 : proceedings of the Sixty-Seventh IEEE Holm Conference on Electrical Contacts}}, isbn = {{978-1-6654-5966-2}}, issn = {{2158-9992}}, keywords = {{Connectors, Resistance, Spectroscopy, Optical microscopy, Microscopy, Vehicle safety, Failure analysis}}, location = {{Tampa, FL, USA}}, pages = {{9 -- 16}}, publisher = {{IEEE}}, title = {{{The Analysis of Failure Mechanisms of Electrical Connectors in Long-term Use Field Vehicles}}}, doi = {{10.1109/HLM54538.2022.9969820}}, year = {{2022}}, } @misc{12946, abstract = {{Ostrich meat is characterized by high nutritional value; however, it remains an exotic product in most countries worldwide. In Europe, only few data are available regarding its microbial contamination, prevalence of antimicrobial-resistant bacteria, and safety. Therefore, this study aimed to investigate the microbiological quality and safety of ostrich meat samples (n = 55), each from one animal, produced in Bavaria, Germany. The provided microbiological status of ostrich meat included mesophilic aerobic bacteria, Enterobacteria, and mesophilic yeast and molds. In terms of food safety, all meat samples were negative for Salmonella spp. and Trichinella spp. Additionally, meat samples and a further 30 stool samples from 30 individuals were investigated for Shiga toxin-producing Escherichia coli genes, with two meat samples that were qPCR-positive. Antimicrobial-resistant Enterobacteriaceae, Enterococcus faecalis, and Enterococcus faecium strains were from meat and stool samples also analyzed; 13 potentially resistant Enterobacteriaceae (meat samples) and 4 Enterococcus faecium (stool samples) were isolated, and their susceptibility against 29 and 14 antimicrobials, respectively, was characterized. The results of this study provide an overview of microbial loads and food safety aspects that may be used as baseline data for the ostrich meat industry to improve their hygienic quality. However, the implementation of monitoring programs is recommended, and microbiological standards for ostrich meat production should be established.}}, author = {{Beindorf, Philipp-Michael and Kovalenko, Oksana and Ulrich, Sebastian and Geißler, Hanna and Korbel, Rüdiger and Schwaiger, Karin and Dorn-In, Samart and Esteban-Cuesta, Irene}}, booktitle = {{Biology : open access journal}}, issn = {{2079-7737}}, keywords = {{antimicrobial resistance, meat microbiology, Salmonella, STEC, Trichinella}}, number = {{7}}, publisher = {{MDPI}}, title = {{{Investigation of Meat from Ostriches Raised and Slaughtered in Bavaria, Germany: Microbiological Quality and Antimicrobial Resistance}}}, doi = {{10.3390/biology11070985}}, volume = {{11}}, year = {{2022}}, } @inproceedings{6317, abstract = {{The electrical-thermal behavior of an electrical connector is determined by heat generation due to Joule heating and heat absorption by conduction, convection and radiation. Heat flow from the connector to the wire is an important heat absorption mechanism for most electrical connectors. The temperature difference between the connector and the wire at infinity is proportional to the axial heat flow induced into the wire. The purpose of this study is to dimension the electrical resistance of a connector for power distribution by the heat flow into the wire. The heat flow is used as a design factor in order to define the maximum power loss for wires with different cross-section areas. With this approach the maximum acceptable electrical resistance for connectors with different sizes can be estimated in the early stages of the design process.}}, author = {{Blauth, Michael and Berger, Frank and Song, Jian}}, booktitle = {{60th IEEE Holm Conference on Electrical Contacts}}, isbn = {{978-1-4799-6069-9 }}, keywords = {{Wires, Connectors, Temperature measurement, Resistance, Heat transfer, Resistance heating}}, location = {{New Orleans, LA, USA }}, pages = {{192 -- 199}}, publisher = {{IEEE}}, title = {{{Influence of the Electrical Resistance and Wire Size on the Current Carrying Capacity of Connectors}}}, doi = {{10.1109/HOLM.2014.7031043}}, year = {{2014}}, } @inproceedings{2082, abstract = {{A robust vision system for the counterfeit detection of bank ATM keyboards is presented. The approach is based on the continuous inspection of a keyboard surface by the authenticity verification of coded covert surface features. For the surface coding suitable visual patterns on the keyboard are selected while considering constraints from the visual imperceptibility, robustness and geometrical disturbances to be encountered from the aging effects. The system’s robustness against varying camera-keyboard distances, lighting conditions and dirt-and-scratches effects is investigated. Finally, a demonstrator working in real-time is developed in order to publicly demonstrate the surface authentication process.}}, author = {{Iqbal, Taswar and Le, Dinh Khoi and Nolte, Michael and Lohweg, Volker}}, booktitle = {{32nd Annual Conference on Artificial Intelligence Paderborn | September 15 – 18, 2009, accepted for Publication}}, isbn = {{978-3-642-04616-2}}, keywords = {{ATMs, human perception, counterfeit resistance, digital authentication, surface coding, pattern recognition}}, pages = {{347--354}}, publisher = {{Springer}}, title = {{{Human Perception Based Counterfeit Detection for Automated Teller Machines, KI 2009, Artificial Intelligence and Automation }}}, doi = {{https://doi.org/10.1007/978-3-642-04617-9_44}}, volume = {{5803}}, year = {{2009}}, }