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The time-to-failure for oil-impregnated paper (OIP) insulation is governed by two primary aging mechanisms: electrical and thermal. The electrical life can be represented as an Inverse Power Law, where lifetime is inversely proportional to applied electric field. The process of thermal aging on the other hand is established by Arrhenius Law, which relates the rate of aging exponentially to temperature. Due to thermal aging, the structure of insulation is altered owing to chemical changes like oxidation, polymerization, and cellulose degradation. For life estimation of a service-aged high-pressure gas filled (HPGF) cables, electrical endurance tests are normally performed at controlled voltage levels to estimate the time to breakdown. However, it is equally necessary to investigate how thermal aging influence changes in the electrical life of insulation. Therefore, in this paper, firstly short-term ramped stress tests are carried out on elevated thermal aged OIP samples extracted from already field-aged HPGF to find a rough estimate of breakdown voltages at different temperatures. Then, long-term electro-thermal step stress tests are performed on the samples to establish a correlation of temperature on the electrical life of the OIP insulation. The long-term stress tests produce reliable breakdown statistics and Maximum Likelihood Estimation of Inverse Power Law fitted on 2-parameter Weibull distributed breakdown data indicate a reduction of model parameter, n from 13.61 to 7.38 with an increase in temperature from 45 to 75 °C and a constant shape factor, beta of 1.50. The dissipation factor, tandelta related to the aging also shows an increase with temperature across a wide frequency range and is inversely proportional to the breakdown voltage.

Inclusion and accessibility in visualization research have gained increasing attention in recent years. However, many challenges still remain to be solved on the road toward a more inclusive, shared-experience-driven visualization design and evaluation process. In this position paper, we discuss challenges and speculate about potential solutions, based on related work, our own research, as well as personal experiences. The goal of this paper is to start discussions on the role of accessibility and inclusion in visualization design and evaluation., Comment: 8 pages, IEEE VIS BELIV 2022 workshop, preprint

Cellulosic fibre composites from agriculture waste product bast fibre such Empty Fruit Bunch (EFB) oil palm has lower cost than normal softwood fibre and they are great alternative to be considered in insulation papermaking. For this purpose, EFB fibre, kenaf fibre and their blend were used to fabricate electrical presspaper samples through a laboratory papermaking process. The study of physical, mechanical and electrical properties such as cellulosic structure, tensile strength, AC voltage breakdown and lightning impulse breakdown strength were conducted according to the standard testing method of insulation IEC60243-1:2013. From this research, the physical structure, mechanical and electrical behaviour of mixed EFB and kenaf fibre insulation paper are comparable to Kraft paper and qualified the basic criterion to be an electrical insulation paper as required by IEC60641-2 standard. The purposes of this insulation paper produced is to be use in electrical transformers, therefore the same test should be repeated to the insulation paper that have undergone aging process at normal and accelerated operating temperatures.

In this paper, we present a techno-economic analysis of providing a Cooperative, Connected and Automated Mobility (CCAM) use case, namely Cooperative Lane Merging (CLM), in a cross-border environment. Multiple network deployment scenarios are proposed to provide Vehicle to Infrastructure (V2I) connectivity with respect to PC5 Mode 4 – enabled RSUs. Total cost of Ownership (TCO) model together with four revenue models are developed to assess the viability of providing CCAM services in the studied settings. Results show that the higher the number of simultaneous connected cars, the higher the TCO of the required deployment needs to be to meet the defined KPIs and especially for the green field deployment with no existing fibre cable or electricity facilities. Another important insight from this analysis is that only with a high fleet penetration rate of connected vehicles, a viable business case can be achieved.

Memory corruption bugs continue to plague lowlevel systems software, generally written in unsafe programming languages. In order to detect and protect against such exploits, many pre- and post-deployment techniques exist. In this position paper, we propose and motivate the need for a hybrid approach for the protection against memory safety vulnerabilities, combining techniques that can identify the presence (and absence) of vulnerabilities pre-deployment with those that can detect and mitigate such vulnerabilities post-deployment. Our proposed hybrid approach involves three layers: hardware runtime protection provided by capability hardware, software runtime protection provided by compiler instrumentation, and static analysis provided by bounded model checking and symbolic execution. The key aspect of the proposed hybrid approach is that the protection offered is greater than the sum of its parts – the expense of postdeployment runtime checks is potentially reduced via information obtained during pre-deployment analysis. During pre-deployment analysis, static checking can be guided by runtime information.

The power transformer is one of the most important equipments that has a critical role in good electrical power delivery. Ageing of paper insulation inside the transformer is irreversible and hugely related to the operation of power transformer. This study involved inspection data from in-service and out-of-service 150 kV power transformers provided by the Indonesian electric company. The degree of polymerization (DP) of the cellulose paper insulation and furanic compound in the insulating oil can be used to estimate the transformer's lifetime. In this study, the correlation between HI decreasing rate (HI dec_rate ) and the loading factor of 115 transformers historical data was observed. The DP of the transformer paper was predicted (DP pred ) using the ANFIS model using the dielectric characteristics and dissolved gases as input. The results show that the correlation between the DP pred decreasing rate (DP dec_rate ) and the loading factor is more significant than that between the HI dec_rate and the loading factor

Mineral oil has long been used as an insulating liquid in transformers. Natural ester-based oil is an alternative due to its non-toxic and biodegradable characteristics. Then this study compared the rate of degradation of accelerated thermal aging paper impregnated in natural ester oil (NE) with mineral oil (MO) and Gas-to-Liquid (GTL). Sealed glass bottles containing thermally upgraded kraft paper (TUK), kraft paper (KP), pressboard (PB), and oil in an atmospheric environment were aged in an oven at 150 °C within 1344 hours. Observations were made at intervals of 336 hours during the aging. The rate of degradation of the paper was observed through the Degree of Polymerization (DP) test of kraft paper, while the chemical structure of the paper was observed through the Fourier Transform Infrared (FTIR) test of the paper. In addition, acid and moisture tests were also carried out to observe the oil-paper interaction during aging. The depolymerization rate of paper in natural ester oil is smaller compared to other oils. This indicates that NE has better thermal stability and can extend life of the transformer paper. The paper aging rate in MO is similar to GTL Oil because they both are hydrocarbons-based.

The Taguchi method was used to optimize the stack structure of electronic paper displays. The falling ball experiment was performed to analyze the effect of various combinations of cover lenses, optically clear adhesives, and substrates on the impact strength of the module surfaces. The results revealed that the stack structure considerably improved the surface impact resistance. The combination of a glass substrate electronic paper display and a plastic cover lens achieved the highest surface impact resistance.

The current study revolves around development of paper from dhaincha fiber (Sesbania aculeata). Dhaincha is a basically cultivated for improvisation of soil quality. Due to deforestation worldwide, various sources of raw materials are used in paper industries. Indian pulp and paper industry is the world's major paper industry. In this study extraction of dhaincha fiber was done followed by retting, combing, chemical analysis and by making of pulp with dhaincha fiber. The dhaincha pulp was then used for making a paper from dhaincha fiber. The thickness of the dhaincha paper was then tested with paper thickness tester. By doing further processing dhaincha paper can be used commercially by paper industry.

The NIST selection process for standardizing Post-Quantum Cryptography Mechanisms is currently running. Many papers already studied their theoretical security, but the resistance in deployed device has not been much investigated so far. In particular, fault attack is a serious threat for algorithms implemented in embedded devices. One particularly powerful technique is to use safe-error attacks. Such attacks exploit the fact that a specific fault may or may not lead to a faulty output depending on a secret value. In this paper, we investigate the resistance of various Post-Quantum candidates algorithms against such attacks.