cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
VP13-14: Influence of Tensile and Compressive Stresses on Magnetic Property of Amorphous Laminated Sheets
Creators: Xueying Zhu
Yongjian Li*
Yu Dou
Jingming Gao
Publisher: name: IEEE
Year: 2023

Soft Magnetic Materials (Virtual)
Amorphous alloy exhibiting high permeability, high saturation flux density, and low coercivity have been widely investigated as cores of motors and high-frequency transformers. However, in comparison with silicon steel, its magnetic properties are sensitive to stress due to the rolling or stacking in manufacture. The causing additional power loss influences the performance of the equipment. Therefore, it is necessary to clarify the magnetic property of Fe-based amorphous alloys under stress. However, it is difficult to measure the magnetic property of amorphous alloys under stress because a single amorphous ribbon is thin and brittle and has poor ductility. Currently, the measurement of the magnetic properties of amorphous alloys is mostly performed using traditional standards and methods for electrical steel sheets [1]. Meanwhile, most of the existing studies have been carried out at low frequencies, which is not able to apply to high-frequency transformers [2]. In this paper, the magnetic properties of amorphous alloy laminates under stress are performed by using a custom-made single sheet tester device. To provide higher frequencies, the silicon steel core was replaced by a nanocrystalline core, and a servo motor was added to apply pressure to the specimen. The specimen size is W30 mm × t0.31 mm × L150 mm. The range of measurement frequency is from 1KHz to 10KHz, and the range of magnetic flux density is from 0.1T to 1.2 T. The hysteresis loops, maximum permeability, and power loss characteristics of the material loading uniaxial stress on are analyzed. The results show that the maximum strength of the magnetic field (Hm) decreases with tensile stress and increases with compressive stress. Meanwhile, the measured iron losses are analyzed based on statistical loss theory. The iron loss decreases with tensile stress and increases with compressive stress.References: [1] Nakata T, Kawase Y and Nakano M, IEEE Transactions on Magnetics, 23.5,2596-2598(1987) [2] Mizuta, Takahiro, Yoshihiro Tani and Koji Fujiwara, IEEE Transactions on Magnetics ,54.11, 1-5 (2018).
Additional file 1 of Development of a reverse transcription droplet digital PCR (RT-ddPCR) assay for sensitive detection of simian immunodeficiency virus (SIV)
Creators: name: Long, Samuel
name: Berkemeier, Brian
Publisher: name: figshare
Year: 2021
Subjects: subject: Medicine
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Neuroscience
subject: 69999 Biological Sciences not elsewhere classified
subject: Cancer
subject: 110309 Infectious Diseases
subject: FOS: Health sciences
subject: Plant Biology
subject: 60506 Virology
subject: Computational Biology

description: Additional file 1. Supplementary Figure 1. Two step RT-ddPCR test with M-MLV RT. M-MLV RT with gene specific priming condition combination was tested during the reverse transcription step of RT-ddPCR (A: buffer background; B: SIV RNA standard spike). The ddPCR step of both reactions was performed with MGB probe assays. Detailed experimental conditions are listed in Supplementary Table 1. Supplementary Table 1. RT-ddPCR reaction condition and quantification results. Reaction conditions (including the specific procedure applied (i.e. two-step RT-ddPCR), the reverse transcriptase (RT) enzyme used at the RT step, the priming method, the enzyme used at the ddPCR step, and the PCR thermal cycling condition) and quantification results (including SIV input (copies) and count (copies)) are listed.
Signal compound specificity in agrobacterium tumefaciens
Creators: name: Spencer, Paul Anthony
Publisher: name: University of British Columbia
Year: 2010

description: Agrobacterium tumefaciens , a soil-borne gram negative bacterium, is the causative agent of crown gall disease and one of the most promising vectors for genetic engineering in plants. It is known to respond to the presence of certain plant-derived phenolic compounds by expressing an essential set of genes for virulence (vir) (Bolton et al., 1986; Stachel et al., 1985-a). However, only one report has described the isolation and identification of virulence inducing phytochemicals producecd by a host plant (Stachel etal., 1985-a). These compounds are acetosyringone (AS) and a-hydroxyacetosyringone (OH-AS), or 3,5-dimethoxy-4-hydroxy- and α-hydroxy-3,5-dimethoxy-4-hydroxy-acetophenone, respectively. Since these compounds have never previously been reported from plant tissues and are not likely to be of widespread occurrence, it seemed unlikely that these were the only signal compounds for this wide host range pathogen. In addition, the results of Bolton et al. (1986), who found that a mixture of lower molecular weight phenolics could also induce vir gene expression, raised the question as to exactly which chemical structures could act as vir -inducers. This thesis reports a quantitative re-examination of the results of Bolton et al. (1986), describes more fully the structure-activity specificity of vir -induction in a wide host range (WHR) strain of A. tumefaciens than did Stachel et al. (1985-a), and presents results which indicate that WHR Agrobacterium is capable of detecting phytochemicals which are ubiquitous or at least widespread amongst susceptible hosts. The relative vir - inducing activities of the lignin precursors coniferyl and sinapyl alcohols, a variety of cinnamic acid derivatives and two chalcones are presented and discussed in terms of the early events in crown gall tumorogenesis and the sophisticated use of Agrobacterium in Ti plasmid-mediated transformation of plants.
VP3-09: Structural and Magnetic Properties of Hexagonal Ferrite composites with Planar and Perpendicular Anisotropy
Creators: Sonal Singh
Puneet Sharma
and Bhupendra Chudasama
Publisher: name: IEEE
Year: 2023

Hard Magnetic Materials (Virtual)
M-type ferrite possess c-axis anisotropy with high magnetocrystalline anisotropy and moderate permittivity making them suitable for microwave applications in W-band. Z-type and Y-type ferrites have basal plane anisotropy with low coercivity and hence their applications are limited to few GHz only. M-type and Y-type ferrites are plausible candidates due to their ease of processing and wide difference in magnetic properties. Their composite represents Z-type ferrite, which is a superposition of M-type (SrFe12O19) and Y-type (Ba2Co2Fe12O22) structural units. Compared to M and Y-type, Z-type ferrites shows complex phase formation with high sintering temperature. One type of hexaferrite has limited frequency range; therefore, focus has been shifted on development of composite ferrites with contrast magnetic and microwave properties. Such composite provides wider compositional flexibility with tunable properties and can be realized in technological applications such as antenna substrates , EMI shielding and for nonreciprocal devices. In the present work, composites of (x)SrFe12O19(SrM)/(1-x) Ba2Co2Fe12O22(Co2Y) [where x= 0.1,0.2,0.3,0.4] were prepared by solid-state reaction. Effect of exchange coupling on structural, morphological, and magnetic properties have been investigated. XRD patterns confirmed the co-existence of SrM and Co2Y phases. It is interesting to note that with increase in x=0.1 to 0.4 the intensity of diffraction lines along (00l) planes increases dramatically indicating preferential growth. Smooth hysteresis loops without any kink confirmed that SrM/Co2Y phases in composites are exchange-coupled. This signifies that there is cooperative magnetic switching among M-Y spins. Linear increase in magnetization was observed with increasing M content. On the other hand decrease in coercivity was observed due to strong intervening coupling between the phases. Switching of Y-phase magnetic spins at low nucleation field drives away the hard M-phase spins. Single peak in switching field distribution curve (SFD) in composites confirms strong coupling between M and Y phases.References: 1. V.G. Harris, A.S. Sokolov, J. Supercond. Nov. Magn. 32 97–108(2019). 2. E.F. Kneller, R. Hawig, IEEE Trans. Magn. 27 3588–3600 (1991).
VP3-13: Mechanochemical Synthesis of MnBi/Fe3C@C Exchange Coupled Hard Magnetic Nanocomposites
Creators: N. S. Anuraag
S. K. Shaw
C. Upadhyay
and N. K. Prasad;
Publisher: name: IEEE
Year: 2023

Hard Magnetic Materials (Virtual)
Permanent magnets have become indispensable components of several renewable energy technologies, like electric vehicles and wind turbines. Price constraints on rare-earth elements led to the search for viable rare-earth-free, permanent magnetic materials. With a theoretical energy product of 18 MGOe, low-temperature phase (LTP) MnBi appears to be a probable "gap magnet" (with an energy product >5 and <30 MGOe) without rare-earth elements. However, due to their low magnetization values, practical energy products greater than 10 MGOe could not be achieved in bulk MnBi magnets. In this study, nanocomposites of Mn55Bi45/Fe3C@C with improved magnetic properties have been prepared by cryogenic ball milling. Further, the viability of utilizing Fe3C@C as a soft phase in composites of hard and soft magnets was also evaluated. Fe3C@C nanoparticles with an exceptional saturation magnetization of 150 emu/g have been synthesized by solvothermal route followed by calcination. These nanoparticles were added in different proportions (0, 5, 10, 15, and 20 wt%) to Mn55Bi45 powder to cryo-mill. It was found that a 10 weight percent addition provided the most enhanced magnetic properties with HC of 6.6 kOe, MS ~ 57 emu/g and Mr ~35 emu/g, improving MS and Mr values by 37% and 58%, respectively (Figure1). The XRD, TEM, and magnetic analyses corroborate the exchange-coupled nanocomposites. This finding not only opens up the opportunity to use Fe3C@C as a soft phase, a comparatively less oxidation-prone soft phase, in other hard magnetic systems but also paves the way for improving the energy product of the MnBi system.References: 1. Coey J M D Permanent magnets: Plugging the gap Scr. Mater. 67 524–9(2012). 2. Cui J, Kramer M, Zhou L, Acta Mater. 158 118–37 (2018). 3. Zhang D T, Cao S, Yue M, J. Appl. Phys. 109 07A722 (2011).
VP5-05: A Study on Acceleration of SP Decoder Using Reliability of Recording Sequence by Neural Network Based on Parity Check Result in SMR System
Creators: Madoka Nishikawa
Yasuaki Nakamura
Yasushi Kanai
Yoshihiro Okamoto
Publisher: name: IEEE
Year: 2023

Magnetic Recording (Virtual)
We study low-density parity-check (LDPC) coding and iterative decoding using a neural network (NN) in the shingled magnetic recording (SMR) system. The read/write (R/W) channel consists of the granular media shown in [1], [2]. In addition, the system noise defined by the signal-to-noise ratio (SNRS) generates at the reading point, where the SNRS = 21.5dB. Here, isp and iglobal stand for the maximum number of iterations in the sum-product (SP) decoder and turbo equalization, respectively. In the conventional SP decoder with the NN, we updated the reliable γn, and the update parameters were THγ = 0.9 and Wγ = 1.34 [1]. The γn means the transition probability from the previous point to the current point on the trellis diagram for the nth (n = 1 to 3) sub-matrix. The NN outputs the reliability of the recording sequence using s for 3 sub-matrices. When the NN output is greater than THγ or smaller than (1 – THγ), we assume that the decoding result is “1” or “0”, respectively. Also, Wγ means the weight to be multiplied by γn. In the proposed SP decoder with the NN, in order to update more reliable γns, we set THγ and Wγ according to the NN input type, respectively, and realize more effective iterative decoding in the SP decoder. Using the parity check matrix, the NN input type is obtained by modulo 2 addition operation to the hard decision results for the NN input in the row direction and adding the rows determined to be incorrect by the parity check in the column direction [3]. Therefore, we set THγ = 0.6, 0.8, 0.9, and 0.9, respectively, such that the update accuracy for NN input types 0, 1, 2, and 3 is about 0.98. Also, we set Wγ = 1.37, 1.34, 1.34, and 1.34, respectively, such that the bit error rate (BER) shows good performance. Figure 1 shows the number of correct updates for iglobal. Here, we set isp = 6. From the figure, for any iglobal, the number of correct updates is larger for the proposed SP decoder with NN. Figure 2 shows the BER performances for iglobal, where the simulation parameters are the same as those in the previous figure. From the figure, the proposed SP decoder with NN achieves no errors, but the others go into the error floor.References: [1] M. Nishikawa, Y. Nakamura, Y. Kanai, and Y. Okamoto, “A study on accelerating SP decoding by neural network in SMR system,” IEEE Trans. Magn., 2023 (to be published). [2] M. Yamashita, Y. Okamoto, Y. Nakamura, H. Osawa, S. J. Greaves, and H. Muraoka, “Performance evaluation of neuro-ITI canceller using a modified writing process for TDMR,” IEICE Trans. Electron., vol. E96-C, no. 12, pp. 1504−1507, Dec. 2013. [3] M. Nishikawa, Y. Nakamura, Y. Okamoto, H. Osawa, Y. Kanai, and H. Muraoka, “A study on iterative decoding with LLR modulator by parity check information in SMR system, ” IEEE Trans. Magn., vol. 54, no. 11, 3001304, Nov. 2018.
VP12-06: Investigation on sensorless operation of two new fault-tolerant interior permanent magnet motors with tradeoff of fault tolerance and flux-intensifying effects
Creators: Li Zhang
Sisi Deng
Xiaoyong Zhu and Zixuan Xiang
Publisher: name: IEEE
Year: 2023

Sensors, High Frequency Devices, and Power Devices (Virtual)
Owing to the advantages of high-power density, high efficiency, and good fault tolerance, the fault-tolerant interior permanent magnet (FT-IPM) motor is favored for high-reliability applications [1]. To further improve the reliability of the motor system, sensorless control technologies were employed in the FT-IPM motor drive [2]. Most previous studies regarding FT-IPM motors aim to improve fault-tolerant capability but suffer the saliency characteristic problem, which is unfavorable for sensorless control. In [3], to improve the sensorless operation capability, the design idea of flux-intensifying effect was innovatively proposed. Typically, for FT-IPM motors, the fractional slot concentrated-windings (FSCWs) is applied to improve fault tolerance [4]. Yet, the use of FSCWs will increase the cross-axis magnetic circuit coupling, which results in a great challenge to achieving obvious inverse saliency. Thus, how to improve the sensorless operating capacity needs to be solved urgently under the premise of ensuring good fault-tolerant capacity. Inspired by this, two new five-phase FT-IPM motors are developed and compared from perspective of flux-intensifying effect. Fig. 1 shows the configuration of the two proposed motors. The cross-section of the partial rotors, with different rotor structures and slot-pole combinations, are presented in Fig. 2. Then, the proposed motors are compared comprehensively from the aspects of inductance characteristics, fault-tolerant performances, and back-EMF, respectively. Fig. 3 shows d- and q-axis inductance characteristics of two motors vary with q-axis current, showing the flux-intensifying effect. To illustrate the fault-tolerant capacity, Fig. 4 illustrates the winding inductances of phase A. Fig. 5 compares the current responses of the two motors under phase-A short-circuit condition. Finally, Fig. 6 displays the experimental no-load back-EMF waveforms of both prototypes at rated speed, which verifies the effectiveness of the proposed FT-IPM motors with flux-intensifying effect design. More details about the fault-tolerance and sensorless operating performances of two motors with different features analyzed and experimental verification will be presented in the full paper.References: [1] L. Zhang, X. Zhu, and L. Xu, IEEE Trans. Ind. Electron., vol. 69, no. 7, pp. 6688-6699, (2022). [2] L. Zhang, Y. Fan, and C. Li, IEEE Trans. Energy Convers., vol. 33, no. 1, pp. 87–95, (2018). [3] N. Limsuwan, Y. Shibukawa, and D. D. Reigosa, IEEE Trans. Ind. Appl., vol. 47, no. 5, pp. 2004-2012 (2011). [4] Y. Fan, R. Cui, and A. Zhang, IEEE Trans. Veh. Technol., vol. 69, no. 1, pp. 282-292, (2020).
Solar System Constraints on Gauss-Bonnet Mediated Dark Energy
Creators: name: Amendola, Luca
name: Charmousis, Christos
name: Davis, Stephen C.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Although the Gauss-Bonnet term is a topological invariant for general relativity, it couples naturally to a quintessence scalar field, modifying gravity at solar system scales. We determine the solar system constraints due to this term by evaluating the post-Newtonian metric for a distributional source. We find a mass dependent, 1/r^7 correction to the Newtonian potential, and also deviations from the Einstein gravity prediction for light-bending. We constrain the parameters of the theory using planetary orbits, the Cassini spacecraft data, and a laboratory test of Newton's law, always finding extremely tight bounds on the energy associated to the Gauss-Bonnet term. We discuss the relevance of these constraints to late-time cosmological acceleration.
description: 13 pages
Additional file 3 of Effects of test experience, closed-arm wall color, and illumination level on behavior and plasma corticosterone response in an elevated plus maze in male C57BL/6J mice: a challenge against conventional interpretation of the test
Creators: name: Shoji, Hirotaka
name: Miyakawa, Tsuyoshi
Publisher: name: figshare
Year: 2021
Subjects: subject: Biochemistry
subject: Neuroscience
subject: Physiology
subject: FOS: Biological sciences
subject: Evolutionary Biology
subject: Sociology
subject: FOS: Sociology
subject: Immunology
subject: FOS: Clinical medicine
subject: 69999 Biological Sciences not elsewhere classified
subject: Science Policy
subject: 111714 Mental Health
subject: FOS: Health sciences

description: Additional File 3: Fig. 2. Basal plasma corticosterone levels in male C57BL/6J mice with or without test experience. Male C57BL/6J mice were subjected to a series of behavioral tests, including an assessment of general health and neurological function, a light/dark transition test, and an open field test. Two days after the open field test, blood was collected from mice with test battery experience (n =8) and from naïve mice with no test experience (n = 8). All of the mice were left undisturbed in their home cages before blood collection. Plasma corticosterone concentrations (ng/mL) were measured. Values are the means ± SEM.
VP12-45: High-frequency Loss Modeling of Nanocrystalline Core Considering Nonuniform Distribution of Flux Density
Creators: Wenbin Meng
Changgeng Zhang
Yongjian Li
He Sun and Zhenyu Wan
Publisher: name: IEEE
Year: 2023

Sensors, High Frequency Devices, and Power Devices (Virtual)
In recent years, nanocrystalline cores were used for high-frequency transformers due to the attractive properties of nanocrystalline materials. However, the flux density distribution is nonuniform along the core because the inner and outer reluctance of the core are different [1]. At present, the calculation of core loss in high-frequency transformers mainly uses two methods: loss separation model and empirical formula [2]. But both methods do not consider the nonuniform distribution of flux density in the core, which may cause huge calculation errors of core losses. In this paper, the core losses of U-shape cores with various wound thicknesses are measured and analyzed. The outer profile of the measured core keeps unchanged, and the inner thickness increased. Based on the measurement results, an improved loss separation model is introduced in detail to characterize the nonuniform distribution of flux density through the cross section. Fig. 1 shows the cross section of the core is discretized into several equal segments. The summation of the fluxes in each path is equal to the total flux. Eventually, according to Ohm’s law for magnetic circuit, we can obtain the relationship between reluctance, flux density and shape parameters. That is, the distribution function of the flux density is obtained. The improved model is expressed as the superposition of n layers core loss, and each layer is calculated using the loss separation method. Fig. 2 shows the error comparison between the traditional loss separation model and the improved model under f = 5 kHz, B = 0.5 T. It can be seen that the loss calculation error is low when considering the non-uniform distribution of flux density. The prediction accuracy is improved significantly compared with the traditional model. More details are shown in the full paper.References: [1] Agheb, E. and H. K. Hoidalen, IET Electric Power Applications., vol. 7, pp.381-390(2013) [2] T. Wang and J. Yuan, IEEE Transactions on Magnetics., vol. 58, pp.1-9(2022)
FA-04: Strain- and Strain-gradient-induced Phenomena in Cr2O3
Creators: Oleksandr Pylypovskyi
Publisher: name: IEEE
Year: 2023

Imaging Magnetic Textures at the Nanoscale
Cr2O3 is a rare example of room-temperature magnetoelectric uniaxial antiferromagnets, which renders it to be a perspective material for low-energy-consuming electronics [1]. We study the behavior of domain walls and a possibility of tuning magnetic responses relying on strain and defect nanostructure of Cr2O3 thin films. Complex defects at grain boundaries act as effective pinning sites for domain wall, favoring the appearance of maze-like domains in polycrystalline films with out-of-plane easy axis [2]. Measuring characteristic scales of these domains by Nitrogen vacancy (NV) magnetometry provides a possibility to estimate inter-grain coupling parameters. Combining statistical analysis of domain size with quantification of the fractal dimension of the domain pattern, we determine the effective strength of the exchange coupling between neighboring grains. To reproduce the domain pattern measured by NV magnetometry, it is crucial to have a small amount of ferromagnetic bonds, which in the case of Cr2O3 can be satisfied by local change of ion valence. The statistically quantified material parameters are in agreement with the estimation using machine learning approach [3]. In films epitaxially grown on sapphire, crystal defects relax strain stemming from the substrate and allow obtaining a sizable strain gradient. Cr2O3 films with thickness of 30-50 nm initially grow pseudomorphically to sapphire, and compressive in-plane strain leads to the enhancement of the Neel temperature locally. Dislocations as strain-relaxing sites propagate into the film from the top surface. The latter induces distribution of the Neel temperature along the film thickness and enables irreversible out-of-plane magnetization of flexomagnetic origin. We found the reversible part of flexomagnetism-induced magnetization is determined by the direction of the Neel vector and quantified it via combined magnetotransport and NV magnetometry measurements [4].References: [1] Y. Shiratsuchi, K. Toyoki, R. Nakatani, J. Phys. Cond. Mat. Vol. 33, p. 243001 (2021); J. Han, R. Cheng, L. Liu et al., Nat. Mater. Vol. 22, p. 684 (2023) [2] I. Veremchuk, M. O. Liedke, P. Makushko et al., Small, Vol. 18, p. 2201228 (2022) [3] O. Pylypovskyi, N. Hedrich, A. Tomilo et. al., Phys. Rev. Applied, in press (2023) [4] P. Makushko, T. Kosub, O. Pylypovskyi et al., Nat. Comm., Vol. 13, p. 6745 (2022)
VP8-02: Multilevel Magnetic Synapses Based on Voltage Controlled Ion Migration for Neuromorphic Application
Creators: Monalisha Peda
Zheng Ma
Eva Pellicer
Enric Menéndez
Jordi Sort
Publisher: name: IEEE
Year: 2023

Magnetoelectric Materials (Virtual)
Synaptic devices with synchronized memory and processor are considered the core elements of Neuromorphic computing (NC) for low-power artificial intelligence (AI). So far, most synaptic devices are based on resistive memories, where the device resistance is tuned with applied voltage or current. However, the use of electric current in such resistive devices causes significant power dissipation by Joule heating. Higher energy efficiency has been reported in materials exhibiting voltage control of magnetism (VCM).[1] In particular, voltage-driven ion motion to modulate magnetism (magneto-ionics) is an emerging VCM mechanism that could offer new prospects for low-power implementation of NC.[2,3] In the present work, we exploit the voltage-controlled motion of different ions (such as N3- and O2-) in transition metal nitrides and oxides (i.e., magneto-ionics) to emulate biological synapses, where synaptic weight (presented by sample magnetization) is tuned with pulsed voltage application. In the proposed devices, by carrying out room-temperature magnetometry measurements while electrolyte gating the nitride and oxide thin films, we have realized multilevel non-volatile and reversible magnetic states for analogue computing and high-density storage (see Fig. 1). Moreover, representative synaptic functionalities illustrating both short and long-term plasticity have been successfully emulated. Furthermore, the devices exhibit high dynamic range, excellent retention and remarkable endurance for real-life hardware implementation of NC. This research provides insight into the great potential of magneto-ionics-based synaptic devices for spin-based neuromorphic computing.References: [1] M. Nichterwitz, S. Honnali and K. Leistner, APL Mater., 9, 030903 (2021). [2] S. Martins, J. De Rojas and J. Sort, Nanoscale, 14, 842 (2022) . [3] R. Mishra, D. Kumar, H. Yang, Phys. Rev. Appl., 11, 054065 (2019).
Automatische Führung von Hackgeräten
Creators: name: Meyer, Joachim
name: Hartmann, Paul
Publisher: name: LANDTECHNIK
Year: 1999

description: Die Entwicklung von automatischen Geräteführungen ist eine wesentliche Voraussetzung für den verstärkten Einsatz physikalischer Verfahren der Unkrautregulierung. Ziel des Projektes ist es, grundlegende Anforderungen und Verfahrensweisen einer Geräteführung mit berührungslos arbeitenden Sensoren zu erarbeiten. Für die technische Überprüfung des Regelungsverhaltens wurde eine Versuchsmechanik gebaut, die in ähnlicher Form als Prototyp für ein Praxisgerät dienen kann. Als Haupteinflussfaktor auf das Verhalten einer automatischen Seitenführung stellt sich die Fahrgeschwindigkeit heraus. Zur Geräteführung wurde ein Regler entwickelt, der sich selbsttätig (adaptiv) auf die Regelungsaufgabe einstellt.
description: LANDTECHNIK, Bd. 54 Nr. 3 (1999)
Heißwasser auf Unkrautpflanzen
Creators: name: Kurfeß, Werner
name: Gutberlett, Birgit
name: Kleisinger, Siegfried
Publisher: name: LANDTECHNIK
Year: 1999

description: Die Unkrautregulierung im Obst- und Weinbau ist kosten- und zeitintensiv. Der Einsatz von Herbiziden ist zwar die kostengünstigste Möglichkeit, doch ist er aus ökologischer Sicht kritisch zu bewerten. Der Einsatz von Heißwasser mit Arbeitsgeschwindigkeiten bis zu 6 km/h ist eine alternative Möglichkeit der Unkrautregulierung mit hoher Flächenleistung. Im Rahmen eines Forschungsprojektes wurde ein Prototyp gebaut und in verschiedenen deutschen Obstanbaugebieten eingesetzt. Dabei wurden die Temperaturen in den Pflanzen verschiedener Unkrautarten und unter der Rinde von Apfelbaumstämmchen gemessen.
description: LANDTECHNIK, Bd. 54 Nr. 3 (1999)
Switching mechanism of photochromic diarylethene derivatives molecular junctions
Creators: name: Huang, Jing
name: Li, Qunxiang
name: Ren, Hao
name: Su, Haibin
name: Shi, Q. W.
name: Yang, Jinlong
Publisher: name: arXiv
Year: 2007
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The electronic transport properties and switching mechanism of single photochromic diarylethene derivatives sandwiched between two gold surfaces with closed and open configurations are investigated by a fully self-consistent nonequilibrium Green's function method combined with density functional theory. The calculated transmission spectra of two configurations are strikingly distinctive. The open form lacks any significant transmission peak within a wide energy window, while the closed structure has two significant transmission peaks on the both sides of the Fermi level. The electronic transport properties of the molecular junction with closed structure under a small bias voltage are mainly determined by the tail of the transmission peak contributed unusually by the perturbed lowest perturbed unoccupied molecular orbital. The calculated on-off ratio of currents between the closed and open configurations is about two orders of magnitude, which reproduces the essential features of the experimental measured results. Moreover, we find that the switching behavior within a wide bias voltage window is extremely robust to both substituting F or S for H or O and varying end anchoring atoms from S to Se and Te.
description: 14 pages and 5 figures
VP3-02: The effect of powder shape on the magnetic anisotropy in NdFeB bonded magnets
Creators: Zhongjie Qu
Qiong Wu
Mengkang Zhang
Zhanjia
Wang
Ming Yue*
Weiqiang Liu*
Publisher: name: IEEE
Year: 2023

Hard Magnetic Materials (Virtual)
Bonded magnets consisting of magnetic powders and polymer binders have gained significant attention owing to their near-net shape characteristics and their capability to be shaped into intricate forms, thus finding widespread applications in fields such as electric motors, automobiles, and electronic communications [1,2]. In this paper, the effect of powder shape on the degree of alignment (DOA) for NdFeB bonded magnets fabricated via calendaring molding was investigated. The magnetic measurement results that the magnetic properties perpendicular to the rolling direction were considerably greater than those parallel to the rolling direction, indicating anisotropy in MQA bonded magnets. In contrast, both magnetic properties perpendicular and parallel to the rolling direction were found to be comparable in HDDR bonded magnets, indicating isotropy. In addition, the magnetic properties of MQA bonded magnet were significantly greater than that of HDDR bonded magnet [Fig. 1(b)], despite both powders having comparable magnetic properties [Fig. 1(a)]. Microstructural analysis revealed that partially parallel aligned platelet-shaped particles induced by mechanical stress were present in MQA bonded magnets [Fig. 2(a)], whereas sphere-like particles exhibited a random distribution in HDDR bonded magnets [Fig. 2(b)]. In summary, platelet-shaped particles present a superior magnetic performance in bonded magnets prepared via calendaring molding than that sphere-like particles.References: [1] K. Gandha, I.C. Nlebedim and V. Kunc, Scr. Mater., 183, 91-95(2020) [2] J.J. Tian, S.G. Zhang, and X.H. Qu, Mater. Lett., 68, 212-214(2012)
Entwicklungsumgebungen zur schnellen Reglerdimensionierung
Creators: name: Lang, Thorsten
Publisher: name: LANDTECHNIK
Year: 1999

description: Wie in vielen anderen technischen Branchen ist auch in der Hydraulik oder Landtechnik eine starke Zunahme von geregelten Systemen und ein Anwachsen der technischen Anforderungen an diese Regelkreise festzustellen. Die Ansprüche an eine größere Funktionsvielfalt bei gleichzeitiger Verkürzung der Entwicklungszeiten von Steuergeräten steigen rasant. Mit welchen Werkzeugen sowohl im Forschungsbereich als auch für industrielle Anwendungen heute Regler schnell ausgelegt und in Elektronikeinheiten umgesetzt werden können, soll hier kurz beschrieben werden.
description: LANDTECHNIK, Bd. 54 Nr. 3 (1999)
VP12-38: Phase Shift Investigation of Dual-Three Phase V-Shaped  PMVM for Improved Torque and Power Factor
Creators: Dongze Pang
Xiaoyong Zhu
Zixuan Xiang
Deyang Fan and Tengguang Wang
Publisher: name: IEEE
Year: 2023

Sensors, High Frequency Devices, and Power Devices (Virtual)
In recent years, permanent magnet vernier machine (PMVM) has aroused extensive research, due to merits of high torque density [1]. However, because of the inevitable flux leakage and large number of airgap flux harmonics, PMVM suffers from the poor power factor, which limits the applications of PMVM [2]. Consequently, it has been a hot but challenging issue on how to realize high output torque and improved power factor simultaneously in the research field of PMVM. Therefore, this article proposes a dual three-phase (DTP) V-shaped PMVM (V-PMVM) with the phase shift angle. In the proposed machine, the influence of phase shift angle on machine torque and power factor is investigated in detail. Also, by the purposeful design of phase shift angle, magnetomotive force (MMF) harmonics are eliminated selectively and the phase winding self-inductance could be reduced, it can not only promote power factor but also increase torque and reduce loss, which lays foundation for the application of this kind of motors in electric vehicles. The topology of V-PMVM and the DTP drive control system are shown in Fig. 1 (a). The Fig. 1 (b) reveals the process of armature MMF harmonics elimination by the phase shift angle and the torque generation of V-PMVM. The machine electromagnetic performance is demonstrated in Fig. 2. As presented in Fig. 2 (a), the magnetic density of 30° phase shift reduces the magnetic density saturation most obviously under the condition of just the armature winding working. It is found that 30° phase shift eliminates more MMF harmonics in Fig. 2 (b). As shown in Fig. 2 (c), compared with 0° phase shift, the 30° phase shift average torque improves 6.5%. Stator core loss and rotor loss of 30° phase shift are lowered 13% and 8% than 0° phase shift. The power factor of 30° phase shift is promoted from 0.718 to 0.794 than 0° phase shift in Fig. 2 (d). In conclusion, the dual three-phase V-PMVM with 30° phase shift not only performs higher output torque and lower loss ,but also has improved power factor which has a broad application prospect. More detailed analysis and verification will be presented in the full article.References: [1] K. Du, L. Xu, W. Zhao and G. Liu, "Analysis and Design of a Fault-Tolerant Permanent Magnet Vernier Machine With Improved Power Factor," in IEEE Transactions on Industrial Electronics, vol. 69, no. 5, pp. 4353-4363, May 2022, doi: 10.1109/TIE.2021.3080206. [2] L. Guo, J. Xu, S. Wu, X. Xie and H. Wang, "Analysis and Design of Dual Three-Phase Fractional-Slot Permanent Magnet Motor With Low Space Harmonic," in IEEE Transactions on Magnetics, vol. 58, no. 1, pp. 1-12, Jan. 2022, Art no. 8100112, doi: 10.1109/TMAG.2021.3111752.
Simulation von großvolumigen Reifen
Creators: name: Von Holst, Christian
name: Göhlich, Horst
Publisher: name: LANDTECHNIK
Year: 1999

description: In der Fahrdynamiksimulation ist der Reifen das entscheidende Bindeglied zwischen Fahrzeug und Fahrbahn. Die Anforderungen an die Reifenmodelle sind bei Landmaschinen sehr hoch, da hier zusätzliche Effekte wie Unrundheit und grobstollige Profilierung, große Reifendeformationen und große ungefederte Masse das Schwingverhalten beeinflussen. Der Unterschied zwischen kennlinienbasierten und physikalischen Reifenmodellen wird beschrieben und die Grenzen der Reifenmodelle werden aufgezeigt. Eine Problemlösung durch Kombination verschiedener Reifenmodelle kann hier in Zukunft möglicherweise Abhilfe schaffen.
description: LANDTECHNIK, Bd. 54 Nr. 3 (1999)
Magnetic phases in the correlated Kondo-lattice model
Creators: name: Peters, Robert
name: Pruschke, Thomas
Publisher: name: arXiv
Year: 2007
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We study magnetic ordering of an extended Kondo-lattice model including an additional on-site Coulomb interaction between the itinerant states. The model is solved in the dynamical mean-field theory using Wilson's numerical renormalization group approach as impurity solver. For a bipartite lattice we find at half filling the expected antiferromagnetic phase. Upon doping this phase is gradually suppressed and hints towards phase separation are observed. For large doping the model exhibits ferromagnetism, the appearance of which can at first sight be explained by Rudermann-Kittel-Kasuya-Yosida interaction. However, for large values of the Kondo coupling $J$ significant differences to a simple Rudermann-Kittel-Kasuya-Yosida picture can be found. We furthermore observe signs of quantum critical points for antiferromagnetic Kondo coupling between the local spins and band states.
VP7-03: Wideband Loss Separation Model of Nanocrystalline Materials Considering Microscopic Magnetization Mechanism
Creators: Jiapeng Zhou
Yongjian Li
Changgeng Zhang
Publisher: name: IEEE
Year: 2023

Magnetization Dynamics and Switching (Virtual)
Core loss is an important reason for the increase in the operating temperature of high-frequency transformers, which also directly determines the performance of high-power power electronic equipment [1-2]. So the construction of an accurate and reliable loss model with physical significance is of guiding significance for the design of high-frequency transformers. In several traditional core loss calculation methods, the loss separation model divides the total loss into hysteresis loss, eddy current loss and excess loss, and the physical meaning is relatively clear, but the traditional loss separation model is only suitable for cases that do not consider the skin effect, and the calculation results will have obvious errors as the frequency increases [3]. In this paper, the three types of losses will be analyzed separately, and a more physically meaningful loss model will be constructed by further improving the loss separation formula. By observing the magnetic domain of the quasi-static magnetization process of nanocrystals, as shown in Fig.1. It can be observed that the magnetization process is mainly the magnetization rotation of the magnetic domains, which is manifested as the displacement of the domain wall. A more detailed analysis of magnetic domains is described in full text. In an alternating magnetic field, the magnetic material is repeatedly magnetized, and the power dissipated by the rotational friction of the magnetic domain is the hysteresis loss. Since the traditional loss separation model does not take into account the skin effect, the calculation of eddy current loss can be made more accurate and has more clear physical significance by introducing complex magnetic permeability. In order to obtain the excess loss with more physical significance, six aspects were analyzed, including domain wall bending and non-uniform and non-repetitive domain wall motion etc. Then an excess loss expression is proposed for calculation. Some of the results are shown in Fig.2. A more detailed analysis is described in full text.References: [1] Z. Guo, R. Yu, W. Xu, X. Feng, and A. Q. Huang, “Design and optimization of a 200-kW medium-frequency transformer for mediumvoltage SiC PV inverters,” IEEE Trans. Power Electron., vol. 36, no. 9, pp. 10548–10560, Sep. 2021. [2] M. Mogorovic and D. Dujic, “100 kW, 10 kHz mediumfrequency transformer design optimization and experimental verification,” IEEE Trans. Power Electron., vol. 34, no. 2, pp. 1696–1708, Feb. 2019. [3] D. Eggers, S. Steentjes, and K. Hameyer, “Advanced iron-loss estimation for nonlinear material behavior,” IEEE Trans. Magn., vol. 48, no. 11, pp. 3021–3024, Nov. 2012.
Mehrkörpersimulation an einem Frontmähwerk
Creators: name: Eberle, Carsten
Publisher: name: LANDTECHNIK
Year: 1999

description: Zur Simulation der Bodenanpassungsfähigkeit bei Frontmähwerken kann die Mehrkörpersimulation zur Untersuchung der auftretenden mechanischen Bodenbelastung dienen. Zur Beurteilung der getroffenen Modellannahmen werden Feldversuche mithilfe von künstlichen und natürlichen Hindernissen genutzt. Erste Ansätze auf der Grundlage reiner Starrkörpermodelle zeigen hierbei eine zu geringe Simulationsgüte im Vergleich mit den im Versuch aufgenommenen Messwerten. Fortlaufende Arbeiten binden deshalb elastische Strukturen in die vorhandenen Mehrkörpermodelle ein. Entsprechend validierte Modelle bilden dann die Grundlage zur Analyse des Systems Frontmähwerk.
description: LANDTECHNIK, Bd. 54 Nr. 3 (1999)
Robust manipulation of electron spin coherence in an ensemble of singly charged quantum dots
Creators: name: Greilich, A.
name: Wiemann, M.
name: Hernandez, F. G. G.
name: Yakovlev, D. R.
name: Yugova, I. A.
name: Shabaev, A.
name: Efros, Al. L.
name: Reuter, D.
name: Wieck, A. D.
name: Bayer, M.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Using the recently reported mode locking effect we demonstrate a highly robust control of electron spin coherence in an ensemble of (In,Ga)As quantum dots during the single spin coherence time. The spin precession in a transverse magnetic field can be fully controlled up to 25 K by the parameters of the exciting pulsed laser protocol such as the pulse train sequence, leading to adjustable quantum beat bursts in Faraday rotation. Flipping of the electron spin precession phase was demonstrated by inverting the polarization within a pulse doublet sequence.
description: 5 Pages, 3 figures
Online-Ertragsmessung in Kleegras mit dem Pendulum Meter
Creators: name: Hammen, Volker Carsten
name: Ehlert, Detlef
Publisher: name: LANDTECHNIK
Year: 1999

description: Als Beitrag zur teilflächenspezifischen Bewirtschaftung ist für die kostengünstige Bestimmung der Pflanzenmasse in stehenden Halmkulturen ein mechanischer Sensor (Pendulum Meter) entwickelt worden. Zur Optimierung des Gerätes unter den speziellen Bedingungen eines Kleegrasgemisches wurden relevante Einstellungsparameter dieses Sensors und die erzielte Messgenauigkeit ermittelt. Das Bestimmtheitsmaß des funktionellen Zusammenhangs von Ausschlagwinkel und Pflanzenaufwuchs ist für alle getesteten Parametereinstellungen mit Werten um 0,95 als gut einzuschätzen. Alle untersuchten Parametervarianten erreichten eine Standardabweichung von weniger als 1 Grad und einen Variationskoeffizienten unter 3 %.
description: LANDTECHNIK, Bd. 54 Nr. 3 (1999)
VP3-04: The effect of Nd content on the elemental interdiffusion mechanism of Nd-Dy-Fe-B magnets
Creators: Y. Qin
W. Q. Liu*
Z. J. Wang
H. Chen
R. H. Du
M. Yue*
Publisher: name: IEEE
Year: 2023

Hard Magnetic Materials (Virtual)
At present, the most effective way to improve the coercivity of sintered Nd-Fe-B magnets is to directly add HRE elements Dy/Tb [1]. However, excessive Dy/Tb additions can lead to significant reductions in remanence and magnetic energy product [2]. Therefore, achieving a balance in the composition-structure-property relationship has become a central research objective. This investigation explores the influence of grain boundary continuity on the magnetic properties, microstructure, and interdiffusion mechanism of Nd/Dy elements in Nd-Dy-Fe-B magnets. Two types of magnets were prepared using the dual alloy method: Nd29+xFe69.27-xM0.79B0.94 (X=0, 0.5, M=Cu, Co, Zr, Al) and Dy42.06Fe57.06B0.88, in a 9:1 ratio, denoted as magnets A and B. The X-ray diffraction (XRD) results showed that as the Nd content increased, the main phase inside the magnet did not change and remained as the 2:14:1 phase, but the peak shifted to the right [Fig. 1(a)], indicating that more (Nd, Dy)-Fe-B was formed in magnet B [Fig. 1(c)]. The coercivity of the magnet increased, but the remanence and magnetic energy product decreased [Fig. 1(b)]. During the demagnetization process, a higher magnetic field was required for the irreversible part of magnet B, while the reversible part gradually decreased. This indicates that with the increase of Nd content, a relatively uniform and continuous layer of RE-rich phase formed inside the magnet, which had a good magnetic isolation effect. This helps to increase the high coercivity of the magnet [Fig. 1(d)]. This paper elucidated the influence of the Nd content on the interdiffusion mechanism of Nd-Dy-Fe-B magnets, which has important guiding significance for the preparation of high-performance Nd-Dy-Fe-B magnets.References: [1] X.L. Liu, M.J. Pan and P. Zhang. J. Rare Earths., Vol. 39, p.558-564 (2021). [2] K.H. Bae, T.H. Kim and S.R. Lee. J. Alloys Compd., Vol. 612, p. 183-188 (2014).
Headgroup dimerization in methanethiol monolayers on the Au(111) surface: a density functional theory study
Creators: name: Zhou, Jian-Ge
name: Williams, Quinton L.
name: Hagelberg, Frank
Publisher: name: arXiv
Year: 2007
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: A long-standing controversy related to the dimer pattern formed by S atoms in methanethiol ($CH_{3}SH$) on the Au(111) surface has been resolved using density functional theory. For the first time, dimerization of methanethiol adsorbates on the Au(111) surface is established by computational modeling. For methylthiolate ($CH_{3}S$), it is shown that the S atoms do not dimerize at high coverage but reveal a dimer pattern at intermediate coverage. Molecular dynamics simulation at high coverage demonstrates that the observed dialkyl disulfide species are formed during the desorption process, and thus are not attached to the surface.
description: 6 pages, 2 figures, submitted to Phys. Rev. B
Influence of the four-fermion interactions in (2+1)D massive electrons system
Creators: name: Fernández, Luis
name: Alves, Van Sérgio
name: Gomes, M.
name: Nascimento, Leandro O.
name: Peña, Francisco
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The description of the electromagnetic interaction in two-dimensional Dirac materials, such as graphene and transition-metal dichalcogenides, in which electrons move in the plane and interact via virtual photons in 3d, leads naturally to the emergence of a projected non-local theory, called pseudo-quantum electrodynamics (PQED), as an effective model suitable for describing electromagnetic interaction in these systems. In this work, we investigate the role of a complete set of four-fermion interactions in the renormalization group functions when we coupled it with the anisotropic version of massive PQED, where we take into account the fact that the Fermi velocity is not equal to the light velocity. We calculate the electron self-energy in the dominant order in the $1/N$ expansion in the regime where $m ^ 2 \ll p ^ 2$. We show that the Fermi velocity renormalization is insensitive to the presence of quartic fermionic interactions, whereas the renormalized mass may have two different asymptotic behaviors at the high-density limit, which means a high-energy scale.
description: 11 pages, 5 figures, 1 table
Equation of state for dense hydrogen and plasma phase transition
Creators: name: Holst, Bastian
name: Nettelmann, Nadine
name: Redmer, Ronald
Publisher: name: arXiv
Year: 2007
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: We calculate the equation of state of dense hydrogen within the chemical picture. Fluid variational theory is generalized for a multi-component system of molecules, atoms, electrons, and protons. Chemical equilibrium is supposed for the reactions dissociation and ionization. We identify the region of thermodynamic instability which is related to the plasma phase transition. The reflectivity is calculated along the Hugoniot curve and compared with experimental results. The equation-of-state data is used to calculate the pressure and temperature profiles for the interior of Jupiter.
description: 7 pages, 7 figures, contibution to the 12th International Workshop on the Physics of Non-Ideal Plasmas, Darmstadt, Germany
Dynamikparameter von Grünlandreifen
Creators: name: Böhler, Heinz
name: Schlotter, Volkmar
Publisher: name: LANDTECHNIK
Year: 1999

description: Im Rahmen eines Forschungsprojektes des Lehrstuhls für Landmaschinen der TU München sollen Rumpfbelastungen eines Traktors bei Transportfahrten mithilfe der Mehrkörpersimulation (MKS) berechnet werden. Die Parameter für die Vorder- und Hinterreifen wurden in Zusammenarbeit mit dem Institut für Agrartechnik der Universität Hohenheim auf dortigen Prüfständen gemessen. Das Reifenmodell des MKS-Programms wurde entsprechend erweitert.
description: LANDTECHNIK, Bd. 54 Nr. 3 (1999)