AMZ Driverless: The full autonomous racing system

This paper presents the algorithms and system architecture of an autonomous racecar. The introduced vehicle is powered by a software stack designed for robustness, reliability, and extensibility. To autonomously race around a previously unknown track, the proposed solution combines state of the art techniques from different fields of robotics. Specifically, perception, estimation, and control are incorporated into one high‐performance autonomous racecar. This complex robotic system, developed by AMZ Driverless and ETH Zürich, finished first overall at each competition we attended: Formula Student Germany 2017, Formula Student Italy 2018 and Formula Student Germany 2018. We discuss the findings and learnings from these competitions and present an experimental evaluation of each module of our solution.     

Comparison of the performance of reduced graphene oxide and multiwalled carbon nanotubes based sulfonated polysulfone membranes for electrolysis application

A series of nanocomposites containing reduced graphene oxide (GO) versus multiwalled carbon nanotubes (MWCNTs) as filler contents anchored with sulfonated polysulfone (SPSF) polymer matrix have been successfully prepared by sol–gel technique with up to 0.5 wt%. The influence of reduced GO compared to MWCNTs to enhance conductivity of nanocomposite SPSF membranes for higher efficient water electrolysis applications has been studied. The nanocomposite membranes were characterized using scanning electron microscopy, atomic force microscopy, Raman spectroscopy, transmission electron microscopy, optical microscopy, electrical conductivity, and tensile testing. The membrane porous structure, porosity, and pores uniformity plus the uniformity of dispersion of mixture are investigated. The conductivity of the composite membranes for water electrolysis applications has been characterized using localized probes across the surface. The results show SPSF–GO nanocomposite membranes offer higher conductivity and improved performance than those of SPSF–MCNT. A uniform constant and high current density of 1.39 A/cm² has been achieved in SPSF–GO membrane at 60°C. POLYM. COMPOS. 36:475–481, 2015. © 2014 Society of Plastics Engineers     

PSO-DBNet for Peak-to-Average Power Ratio Reduction Using Deep Belief Network

Data transmission through a wireless network has faced various signal problems in the past decades. The orthogonal frequency division multiplexing (OFDM) technique is widely accepted in multiple data transfer patterns at various frequency bands. A recent wireless communication network uses OFDM in long-term evolution (LTE) and 5G, among others. The main problem faced by 5G wireless OFDM is distortion of transmission signals in the network. This transmission loss is called peak-to-average power ratio (PAPR). This wireless signal distortion can be reduced using various techniques. This study uses machine learning-based algorithm to solve the problem of PAPR in 5G wireless communication. Partial transmit sequence (PTS) helps in the fast transfer of data in wireless LTE. PTS is merged with deep belief neural network (DBNet) for the efficient processing of signals in wireless 5G networks. Result indicates that the proposed system outperforms other existing techniques. Therefore, PAPR reduction in OFDM by DBNet is optimized with the help of an evolutionary algorithm called particle swarm optimization. Hence, the specified design supports in improving the proposed PAPR reduction architecture.     

Design and Synthesis of DNA‐Interactive β‐Carboline–Oxindole Hybrids as Cytotoxic and Apoptosis‐Inducing Agents

A new series of (E)‐3‐[(1‐aryl‐9H‐pyrido[3,4‐b]indol‐3‐yl)methylene]indolin‐2‐one hybrids were synthesized and evaluated for their in vitro cytotoxic activity against a panel of selected human cancer cell lines, namely, HCT‐15, HCT‐116, A549, NCI‐H460, and MCF‐7, including HFL. Among the tested compounds, (E)‐1‐benzyl‐5‐bromo‐3‐{[1‐(2,5‐dimethoxyphenyl)‐9H‐pyrido[3,4‐b]indol‐3‐yl]methylene}indolin‐2‐one ( 10 s ) showed potent cytotoxicity against HCT‐15 cancer cells with an IC₅₀ value of 1.43±0.26 μm and a GI₅₀ value of 0.89±0.06 μm . Notably, induction of apoptosis by 10 s on the HCT‐15 cell line was characterized by using different staining techniques, such as acridine orange/ethidium bromide (AO/EB) and DAPI. Further, to understand the mechanism of anticancer effects, various assays such as annexin V‐FITC/PI, DCFDA, and JC‐1were performed. The flow cytometric analysis revealed that compound 10 s arrests the HCT‐15 cancer cells at the G0/G1 phase of the cell cycle. Additionally, western blot analysis indicated that treatment of 10 s on HCT‐15 cancer cells led to decreased expression of anti‐apoptotic Bcl‐2 and increased protein expression of both pro‐apoptotic Bax and caspase‐3, ‐8, and ‐9, and cleaved PARP with reference to actin. Next, a clonogenic assay revealed the inhibition of colony formation in HCT‐15 cancer cells by 10 s in a dose‐dependent manner. Moreover, upon testing on normal human lung cells (HFL), the compounds were observed to be safer with a low toxicity profile. In addition, viscosity and molecular‐docking studies showed that compound 10 s has typical intercalation with DNA.     

Variation of lexan polycarbonate properties by electron beam

The modifications in microstructural, optical, and photoluminescence properties of the Lexan polycarbonate (bisphenol‐A‐polycarbonate) films exposed to different electron doses have been studied using UV–vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), positron annihilation lifetime spectroscopy, photoluminescence spectroscopy, and scanning electron microscopy (SEM). The obtained UV–vis spectroscopy results showed decrease in optical energy gap, optical activation energy, and increase in number of carbon atoms per cluster with increase in electron dose. The chemical changes in electron irradiated polymers due to chain scission and reconstruction have been observed from FTIR spectroscopy. The correlation of positron lifetime study with optical measurement is obtained, and electron irradiation‐induced microstructural modifications within the polymer is understood. SEM result shows the degradation of Lexan polymer after electron irradiation. The mechanical properties and average molecular weight of Lexan decrease after irradiation, whereas average number of chain scissions per original polymer molecule increases. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Hydrogen production by alcoholysis of sodium borohydride

Alcoholysis of sodium borohydride offers advantages due to reduction in number of steps for recycling of sodium borohydride, elimination of freezing problems that are associated with the use of water, fast generation of hydrogen, etc. Methanol was used to liberate hydrogen from sodium borohydride. The influence of the amount of solvent, substrate concentration, temperature and catalyst on the kinetics of alcoholysis reaction in non‐stabilized sodium borohydride has been examined in the present study. The reaction was found to be first order with respect to substrate concentration and zero order with respect to solvent concentration. Effect of soluble metal salts, metal powder and metal boride as catalysts on hydrogen generation rate has also been investigated. It was found that NiCl₂, Ni₂B and RuCl₃ were effective catalysts and hydrogen generation proceeds with high efficiency in the presence of these catalysts. Copyright © 2013 John Wiley & Sons, Ltd.