bluuebunny/crossref_metadata_2025 huggingface dataset:
Prey-catching behaviour and echolocation in the Australian Ghost Bat, Macroderma gigas (Microchiroptera: Megadermatidae).
Authors: Kulzer E. , Nelson J. E. , McKean J. L. , Moehres F. P.
Published: December 2022

The prey-catching behaviour of Macroderma gigas was investigated under laboratory conditions using Mice. The echolocation pulses were very short, broad-banded and downwardly modulated with four harmonics, the first of which was usually weak and the second and third strong. These pulses were emitted either singly or in groups. Sounds from live Mice (vocalisations or sounds made by their movements) caused the hanging bats to direct their pinnae at the sound source and to move them backwards and forwards. These movements were usually not accompanied by echolocation pulses. The ultrasonic cries of infant Mice produced these responses with minimum delay. After listening to the sounds of the prey for varying periods, depending on the amount of noise the prey made, the bat emitted echolocation pulses that reached a peak frequency just before take-off on a varying number of reconnoitre flight s past the prey and back to the perch. The final attack was made from the perch or from a hover during a reconnoitre flight. The captured Mice were taken back to the perch to be eaten. Macroderma gigas was able to locate live Mice placed in: 1, one of two to eight tubs in dim light; 2, in one of two tubs covered with nylon gauze so that the Mice could not be seen; and 3, in one of two tubs covered by gauze and wood so that they could not be seen or echolocated. They also differentiated between noises from live Mice and replayed recordings of these noises. Silent and motionless Mice were not detected. The evidence presented suggests that passive acoustic localisation is an important part of prey-catching in M. gigas.
New fossil localities for Macroderma (Chiroptera: Megadermatidae) in New South Wales and its past and present distribution in Australia.
Authors: Molnar R . E. , Hall L. S. , Mahoney J. H.
Published: December 2022

Remains of the Ghost Bat Macroderma gigas (Dobson, 1880) are reported from cave deposits at Cliefden, Wellington and Yessabah Caves, New South Wales. These localities lie well south of the previously known range for M. gigas in eastern Australia. Another specimen, from Ashford Cave, N.S.W. , can be identified only as Macroderma sp. All are Quaternary in age. Remains of M. gigas dating from this time are also known from South Australian and Western Australian localities south of the area where the species now occurs. The Ghost Bat is presently found in Queensland, the Northern Territory and as far south as latitude 28oS in Western Australia. Its environments range from dry, hot mulga country to humid, hot rainforest. Previous understanding of the factors limiting the range of M. gigas is inadequate and microclimates of the caves used by this bat may be an important factor.
Diet and habitat preference of Leggadina forresti (Rodentia: Muridae) in western New South Wales.
Authors: Read D. G.
Published: December 2022

NA
Influxes of the grey-headed flying-fox Pteropus poliocephalus (Chiroptera, Pteropodidae) to Victoria in 1981 and 1982.
Authors: Menkhorst P. W. , Dixon J. M.
Published: December 2022

NA
Small mammal communities in temperate North American forests.
Authors: Jr. Kirkland G. L.
Published: December 2022

Small mammal communities in temperate North American forests typically are dominated by three families: Soricidae, Sciuridae, and Cricetidae. Omnivores and insectivores predominate in such communities, with herbivores and granivores representing minor trophic elements. Small mammal diversity often is greater than generally ack nowledged, especially in forests having mixtures of boreal and austral elements. With the exception of shrews of the genus Sorex , coexistence of congeners is uncommon among small mammals in temperate North American forests.
Small mammal communities in Australian temperate heathlands and forests.
Authors: Fox B. J.
Published: December 2022

Temperate heathlands and forests in Australia are largely restricted to the eastern, southern and south-western coastal margins. Although a small macropodid may be included in some forests the small-mammal assemblages are commonly species from only two metatherian families, bandicoots and dasyurids, and one eutherian family, murid rodents. These native rodents divide into 'old endemics' (Pseudomys, Mastacomys and Melomys) and 'new endemics' (Rattus). Introduced species fill the niches of absent natives rather than 'new' niches, implying few unused resources in these communities. The basic community has one species of Rattus, one dasyurid and one bandicoot and usually one 'old endemic'; additional species from each group are added when greater resources are available. Abundance is low overall, and may reflect reduced productivity; species richness and diversity are usually greater in heathland, but densities are greater in forests and may result from the lower nutrient levels in heathlands. There is a negative correlation between species diversity and latitude, although species diversity depends more on local variables such as habitat diversity. Tasmania has a less diverse fauna, but this may be an island effect as the abundance is generally increased.
Small mammal assemblages in arid Australia: a reappraisal.
Authors: Morton S. R. , Baynes A.
Published: December 2022

Previous interpretations of small mammal assemblages in arid Australia are reappraised in the light of new knowledge. First, analysis of skeletal remains from the surfaces of cave deposits at 15 sites in the western ariel zone shows that species richness of rodents and polyprotoclont marsupials has declined to 44% and 41% of the pre-European numbers. Those species that survived European settlement tend to be small or to inhabit rocky outcrops. We suggest that the extinctions preferentially occurred among species that were more specialised in habitat or diet: the remaining species are relatively opportunistic (or r-selected). Consequently, current perceptions that "plagueing" species dominate small mammal assemblages were probably not true of the original fauna. Second, studies of seedeating animals in arid Australia suggest that birds and ants are the principal granivores because their body-plans best suit them to an uncertain seed supply resulting from climatic peculiarities; there is no evidence that they have excluded rodents from the seed resource over evolutionary time. Few Australian desert-dwelling rodents appear to be specialised granivores, probably because of the variability in seed supply. We suggest that the preponderance of work conducted on North American heteromyicl rodents has led to a misplaced assumption that granivory is the most successful way of life for desert-dwelling rodents, and that the prominence of omnivory and insectivory in Australia demonstrates that different arid ecosystems favour different trophic strategies among small mammals.
Predation on a platypus, Ornithorhynchus anatinus (Monotremata: Ornithorhynchidae), by a goshawk.
Authors: Richards G. C.
Published: December 2022

NA
The presence of rostral palatal taste buds in mammals.
Authors: Kratzing J. E.
Published: December 2022

NA
Twins in the western grey kangaroo, Macropus fuliginosus (Marsupialia: Macropodidae), in north-western Victoria.
Authors: Norbury G. L.
Published: December 2022

NA
Current Literature.
Authors: Calaby J. H.
Published: December 2022

NA
Notes on the flying-fox, Pteropus melanotus (Chiroptera: Pteropodidae), on Christmas Island, Indian Ocean.
Authors: Tidemann C. R.
Published: December 2022

NA
Vision in flying foxes (Chiroptera: Pteropodidae).
Authors: Graydon M. L. , Giorgi P. P. , Pettigrew J. D.
Published: December 2022

NA
Lead poisoning in flying-foxes (Chiroptera: Pteropodidae).
Authors: Sutton R. H. , Hariono B.
Published: December 2022

NA
Summary and recommendations to the first national flying-fox symposium.
Authors: Nelson J. E.
Published: December 2022

NA
Detectability of the feathertail glider, Acrobates pygmaeus (Marsupialia: Burramyidae), in relation to measured weather variables.
Authors: Goldingay R. L. , Kavanagh R. P.
Published: December 2022

NA
A new view of the relationships of Australian and American marsupials.
Authors: Richardson B. J.
Published: December 2022

NA
Diet of the Squirrel Glider, Petaurus norfolcensis (Marsupialia: Petauridae), in Victoria.
Authors: Menkhorst P. W. , Collier M.
Published: December 2022

Analysis of faecal pellets from Petaurus norfolcensis in northern and central Victoria showed that it ate insects, principally Coleoptera and lepidopteran larvae obtained from the foliage of Eucalyptus and Acacia, and plant exudates, especially Eucalyptus sap and Acacia gum. Diet was broadly similar to that of its congeners P. australis and P. breviceps but differed in the ubiquitous presence of insect remains, the preponderance of caterpillars (particularly the noxious Doratifera sp.) and the relative insignificance of spiders. Eucalyptus nectar and pollen, as well as lerps, which are important to other Petaurus spp. elsewhere, appeared to be less important components of the diet of P. norfolcensis at our main study site. This result was probably due to these food items being unavailable when we collected the pellets. The items were heavily utilised at another site. The availability of pollen and nectar may be irregular and unpredictable in eucalypt open forests of low species diversity. Absence of this rich source of protein and nitrogen may be partially compensated for by the relatively high diversity and density of foliage invertebrates.
Tolerance of pouch young kangaroos (Macropodidae) for cows' milk and milk replacers containing different amounts of glucose or lactose.
Authors: Walker D. M. , Vickery K.
Published: December 2022

Young Red (Macropus rufus) and Eastern Grey (M. giganteus) Kangaroos, aged between 150-190 days and between 200-250 days of age respectively at the start of the experiments, were obtained after their mothers had been shot by commercial shooters. A system of housing was developed so that they could be fed continuously by stomach tube and balance experiments performed. Experiment 1: Three joeys were each given six diets which contained (expressed as a proportion of total energy) either 6.6%, 13.3% or 20.0% of glucose or lactose. Measurements of dry matter excretion in faeces plus urine showed a decrease in dry matter utilisation at the two highest levels of lactose. Diarrhoea occurred in all joeys given the highest levels of lactose. No diarrhoea occurred in the joeys given equivalent amounts of glucose. Volatile fatty acid excretion was positively correlated with lactose intake. Experiment 2: Four joeys were given reconstituted dried whole cows' milk to provide a lactose intake similar to that given in experiment I at the intermediate level. Since cows' milk contains approximately 26% energy as lactose, the intake of milk had to be restricted severely. One joey developed diarrhoea. Experiment 3: Four joeys were given a carbohydrate-free milk replacer to provide control data for experiments I and 2. The chance occurrence of spontaneous bone fractures in two joeys after 5 weeks on the experiment necessitated an investigation of mineral utilisation. It was concluded that mineral requirements are very high in later pouch life and that tolerance for cows' milk and for lactose is limited to an intake of < 6.5 g lactose kg-1 d-1, or < 11-12 g d-1 for kangaroo joeys between 1.4-3.0 kg live weight.
Chert oxygen isotope ratios are driven by Earth's thermal evolution
Authors: Tatzel M. , Frings P. J. , Oelze M. , Herwartz D. , Lünsdorf N. K. , Wiedenbeck M.
Published: December 2022

The
18
O/
16
O ratio of cherts (δ
18
O
chert
) increases nearly monotonically by ~15‰ from the Archean to present. Two end-member explanations have emerged: cooling seawater temperature (T
SW
) and increasing seawater δ
18
O (δ
18
O
sw
). Yet despite decades of work, there is no consensus, leading some to view the δ
18
O
chert
record as pervasively altered. Here, we demonstrate that cherts are a robust archive of diagenetic temperatures, despite metamorphism and exposure to meteoric fluids, and show that the timing and temperature of quartz precipitation and thus δ
18
O
chert
are determined by the kinetics of silica diagenesis. A diagenetic model shows that δ
18
O
chert
is influenced by heat flow through the sediment column. Heat flow has decreased over time as planetary heat is dissipated, and reasonable Archean-modern heat flow changes account for ~5‰ of the increase in δ
18
O
chert
, obviating the need for extreme T
SW
or δ
18
O
sw
reconstructions. The seawater oxygen isotope budget is also influenced by solid Earth cooling, with a recent reconstruction placing Archean δ
18
O
SW
5 to 10‰ lower than today. Together, this provides an internally consistent view of the δ
18
O
chert
record as driven by solid Earth cooling over billion-year timescales that is compatible with Precambrian glaciations and biological constraints and satisfyingly accounts for the monotonic nature of the δ
18
O
chert
trend.
Meiotic nuclear pore complex remodeling provides key insights into nuclear basket organization
Authors: King Grant A. , Wettstein Rahel , Varberg Joseph M. , Chetlapalli Keerthana , Walsh Madison E. , Gillet Ludovic C.J. , Hernández-Armenta Claudia , Beltrao Pedro , Aebersold Ruedi , Jaspersen Sue L. , Matos Joao , Ünal Elçin
Published: December 2022

Nuclear pore complexes (NPCs) are large proteinaceous assemblies that mediate nuclear compartmentalization. NPCs undergo large-scale structural rearrangements during mitosis in metazoans and some fungi. However, our understanding of NPC remodeling beyond mitosis remains limited. Using time-lapse fluorescence microscopy, we discovered that NPCs undergo two mechanistically separable remodeling events during budding yeast meiosis in which parts or all of the nuclear basket transiently dissociate from the NPC core during meiosis I and II, respectively. Meiosis I detachment, observed for Nup60 and Nup2, is driven by Polo kinase-mediated phosphorylation of Nup60 at its interface with the Y-complex. Subsequent reattachment of Nup60-Nup2 to the NPC core is facilitated by a lipid-binding amphipathic helix in Nup60. Preventing Nup60-Nup2 reattachment causes misorganization of the entire nuclear basket in gametes. Strikingly, meiotic nuclear basket remodeling also occurs in the distantly related fission yeast, Schizosaccharomyces pombe. Our study reveals a conserved and developmentally programmed aspect of NPC plasticity, providing key mechanistic insights into the nuclear basket organization.
cDC1-derived IL-27 regulates small intestinal CD4+ T cell homeostasis in mice
Authors: Ahmadi Fatemeh , Junghus Fredrik , Ashworth Christian , Lappalainen Amanda , Mörbe Urs , Kotarsky Knut , Agace William W.
Published: December 2022

The small intestinal lamina propria contains large numbers of IFNγ-producing T helper (Th1) cells that play important roles in intestinal homeostasis and host defense, but the mechanisms underlying their development remain poorly understood. Here, we demonstrate that Th1 cells accumulate in the SI-LP after weaning and are maintained there long term. While both Th17 and Th1 cell accumulation in the SI-LP was microbiota dependent, Th1 cell accumulation uniquely required IL-27 and MHCII expression by cDC1. This reflected a requirement for IL-27 signaling in the priming of Th1 cells rather than for their maintenance once in the mucosa. cDC1-derived IL-27 was essential for maintaining the Th1–Th17 balance within the SI-LP, and in its absence, remaining Th1 cells expressed enhanced levels of Th17 signature genes. In conclusion, we identify cDC1-derived IL-27 as a key regulator of SI-LP Th1–Th17 cell homeostasis.
Progressive differentiation toward the long-lived plasma cell compartment in the bone marrow
Authors: Koike Takuya , Fujii Kentaro , Kometani Kohei , Butler Noah S. , Funakoshi Kenji , Yari Shinya , Kikuta Junichi , Ishii Masaru , Kurosaki Tomohiro , Ise Wataru
Published: December 2022

The longevity of plasma cells is dependent on their ability to access and reside in so-called niches that are predominantly located in the bone marrow. Here, by employing a traceable method to label recently generated plasma cells, we showed that homeostatic plasma cells in the bone marrow and spleen were continuously replenished by newly generated B220hiMHC-IIhi populations that progressively differentiated into B220loMHC-IIlo long-lived plasma cell (LLPC) populations. We also found that, in the bone marrow, germinal center (GC)–independent and GC-dependent plasma cells decayed similarly upon NP-CGG engagement, and both entered the B220loMHC-IIlo LLPC pool. Compared with NP+B220hiMHC-IIhi plasma cells, NP+B220loMHC-IIlo cells were more immobilized in the bone marrow niches and showed better survival potential. Thus, our results suggest that the adhesion status of bone marrow plasma cells is dynamically altered during their differentiation and is associated with provision of survival signals.
Uniqueness of orders and parameters in multi-term time-fractional diffusion equations by short-time behavior
Authors: Liu Yikan , Yamamoto Masahiro
Published: December 2022

As the most significant difference from parabolic equations, long-time or short-time behavior of solutions to time-fractional evolution equations is dominated by the fractional orders, whose unique determination has been frequently investigated in literature. Unlike all the existing results, in this article we prove the uniqueness of orders and parameters (up to a multiplier for the latter) only by principal terms of asymptotic expansions of solutions near t = 0 at a single spatial point. Moreover, we discover special conditions on unknown initial values or source terms for the coincidence of observation data. As a byproduct, we can even conclude the uniqueness for initial values or source terms by the same data. The proof relies on the asymptotic expansion after taking the Laplace transform and the completeness of generalized eigenfunctions.
Microscopic dynamics and Bose–Einstein condensation in liquid helium
Authors: Trachenko K
Published: December 2022

We review fundamental problems involved in liquid theory including both classical and quantum liquids. Understanding classical liquids involves exploring details of their microscopic dynamics and its consequences. Here, we apply the same general idea to quantum liquids. We discuss momentum condensation in liquid helium which is consistent with microscopic dynamics in liquids and high mobility of liquid atoms. We propose that mobile transit atoms accumulate in the finite-energy state where the transit speed is close to the speed of sound. In this state, the transit energy is close to the oscillatory zero-point energy. In momentum space, the accumulation operates on a sphere with the radius set by interatomic spacing and corresponds to zero net momentum. We show that this picture is supported by experiments, including the measured kinetic energy of helium atoms below the superfluid transition and sharp peaks of scattered intensity at predicted energy. We discuss the implications of this picture including the macroscopic wave function and superfluidity.
Application of novel hybrid machine learning systems and radiomics features for non-motor outcome prediction in Parkinson’s disease
Authors: Salmanpour Mohammad R , Bakhtiyari Mahya , Hosseinzadeh Mahdi , Maghsudi Mehdi , Yousefirizi Fereshteh , Ghaemi Mohammad M , Rahmim Arman
Published: December 2022

Objectives.Parkinson’s disease (PD) is a complex neurodegenerative disorder, affecting 2%–3% of the elderly population. Montreal Cognitive Assessment (MoCA), a rapid nonmotor screening test, assesses different cognitive dysfunctionality aspects. Early MoCA prediction may facilitate better temporal therapy and disease control. Radiomics features (RF), in addition to clinical features (CF), are indicated to increase clinical diagnoses, etc, bridging between medical imaging procedures and personalized medicine. We investigate the effect of RFs, CFs, and conventional imaging features (CIF) to enhance prediction performance using hybrid machine learning systems (HMLS).Methods.We selected 210 patients with 981 features (CFs, CIFs, and RFs) from the Parkinson’s Progression-Markers-Initiative database. We generated 4 datasets, namely using (i), (ii) year-0 (D1) or year-1 (D2) features, (iii) longitudinal data (D3, putting datasets in years 0 and 1 longitudinally next to each other), and (iv) timeless data (D4, effectively doubling dataset size by listing both datasets from years 0 and 1 separately). First, we directly applied 23 predictor algorithms (PA) to the datasets to predict year-4 MoCA, which PD patients this year have a higher dementia risk. Subsequently, HMLSs, including 14 attribute extraction and 10 feature selection algorithms followed by PAs were employed to enhance prediction performances. 80% of all datapoints were utilized to select the best model based on minimum mean absolute error (MAE) resulting from 5-fold cross-validation. Subsequently, the remaining 20% was used for hold-out testing of the selected models.Results.When applying PAs without ASAs/FEAs to datasets (MoCA outcome range: [11,30]), Adaboost achieved an MAE of 1.74 ± 0.29 on D4 with a hold-out testing performance of 1.71. When employing HMLSs, D4 + Minimum_Redundancy_Maximum_Relevance (MRMR)+K_Nearest_Neighbor Regressor achieved the highest performance of 1.05 ± 0.25 with a hold-out testing performance of 0.57.Conclusion.Our study shows the importance of using larger datasets (timeless), and utilizing optimized HMLSs, for significantly improved prediction of MoCA in PD patients.
Retracted: Exact solutions of the Schrödinger equation using extended Nikiforov-Uvarov formalism for generalized pseudo-harmonic oscillator
Authors: Alrebdi H I , Ikot A N , Okorie U S , Obagboye L F , Horchani R , Abdel-Aty A-H
Published: December 2022

The Schrodinger equation with generalized pseudo-harmonic oscillator (GPHO) is transformed into a form that is compatible with extended Nikiforov-Uvarov (ENU) formalism, and its exact solutions are obtained in three and N-dimensions using this formalism. The energy spectrum for the GPHO was obtained in closed form, and the wave function was determined using the biconfluent Heun differential equation. Special cases are deduced, and some numerical results are shown to illustrate the behaviour of the bound state energies at different quantum states for various values of potential parameter; lambda. In addition, the thermodynamic property expressions for GPHO are obtained in closed form, and their variation with temperature-dependent parameters is discussed extensively for various values of lambda. Our results agree with those obtained in the literatures.
Low-temperature, short-time, wafer-level bonding for Cu/Sn/Cu solid-state-diffusion interconnect in 3-D integration
Authors: Li Xueru , Wang Junqiang , Li Mengwei , Hou Wen
Published: December 2022

In this paper, Cu/Sn/Cu solid-state diffusion (SSD) under low temperature is proposed and investigated for three-dimensional (3-D) integration. Cu and Sn films were deposited by high-efficiency and low-cost physical vapor deposition to fabricate 40-μm-pitch daisy-chain structures. Subsequently, the Cu bump surface was treated with Ar (5% H2) plasma. The Cu/Sn/Cu structure was bonded face to face at 200 °C for 15 min The interfacial composition of the as-bonded dies comprised five layers, Cu/Cu3Sn/Cu6Sn5/Cu3Sn/Cu, with no Sn remaining and no overflow. After annealing at 200 °C for 15 min under N2 atmosphere, as the Cu6Sn5 completely transformed into Cu3Sn, the microstructure changed to stable three layers: Cu/Cu3Sn/Cu. Additionally, the average bonding shear strength reached 27.0 MPa, which is higher than that for conventional Cu/Sn SSD bonding. The measured bonding resistance value was maintained at the theoretical value. Moreover, the parabolic growth constant of Cu3Sn reached 1.86 × 10−15 m2/s. Our study demonstrates the feasibility of using Cu/Sn/Cu SSD for low-temperature, short-time, wafer-level bonding.
Stability for an inverse source problem of the diffusion equation
Authors: Yao Xiaohua , Zhao Yue
Published: December 2022

We prove an increasing stability estimate for an inverse source problem of the diffusion equation with a nontrivial variable absorption coefficient in

R

3

. The stability estimate consists of two parts: the Lipschitz type data discrepancy and the high frequency tail of the source function. The latter decreases when the upper bound of the frequency increases. The proof is based on an exact observability bound for the heat equation and the resolvent estimates for the elliptic operator. In particular, to justify the Fourier transform and obtain Plancherel’s theorem for the time-domain Cauchy data on the boundary, we derive certain appropriate time decay estimates for the heat equation using semigroup theory.
Carbon ion beam induced chemical modification and nano-pyramid growth on Si surface
Authors: Bhowmick Sudip , Mukherjee Joy , Ghosal Manorama , Karmakar Prasanta
Published: December 2022

We report the growth of nano-ripple on, initially smooth Si surface due to chemically guided additional instability generation during 10 keV C+ bombardment at grazing (70°) ion incidence. Also, the transformation of the ripple structure to triangular nano-pyramidal structure at higher ion fluence is investigated in details. It is shown that the chemical nature of the surface changes due to silicon carbide formation at the ion impact sites, and the surface becomes a mixture of Si and SiC. The differential sputtering of Si from pure Si and SiC, generates an additional instability which leads to trigger the ripple pattern on the surface. The variation of height amplitude, lateral correlation length and slope angles of the developed structures are investigated and explained in terms of existing continuum theory. At very high ion fluence the transformation of the structure into three dimensional triangle (pyramidal) is revealed and the mechanism is explained in the light of variation of local ion impact angle and its consequent effects.
Atomistic approach for predicting mechanical properties and creep behavior of graphene reinforced natural rubber composites
Authors: Hussain Syed Asad , Sharma Sumit , Patel Pramod Rakt
Published: December 2022

Graphene has proven to be one of the finest nanomaterials for rubber. In the present study the effect of volume fraction and functionalization of graphene sheets on the mechanical properties and creep behavior of natural rubber (NR) composites has been predicted using the molecular dynamics approach. The properties of NR nanocomposite with the graphene sheet volume fractions of 2.5%, 4.72%, and 11.35% have been compared with the properties of pristine NR. It was observed that the values of Young’s modulus, bulk modulus, and shear modulus were increased up to 104%, 68.40%, and 17.5% respectively for the NR nanocomposite with the reinforcement of 11.35% of graphene compared to pristine NR. The ultimate tensile strength was also increased up to 46% with a higher volume fraction of the graphene sheet. The carboxyl and ester functional groups were used for the functionalization of the graphene sheet. Among the two groups, it was observed that the carboxyl group functionalized graphene sheet provided a better result than the ester group functionalized graphene sheet reinforced NR nanocomposite. The results showed that the introduction of graphene sheets improved the creep resistance of NR nanocomposites significantly. The pristine NR reached the failure stage in just 600 ps for the stress level of 140 MPa, whereas the NR nanocomposite with an 11.35% volume fraction sustained a higher stress level of 160 MPa and has not shown any sign of failure, even after the simulation time of 1000 ps.
Spherical near-field measurement of the offset vehicle antenna mounted on a vehicle
Authors: Wu Jinxin , Zhu Yun , Wang Weilong , Liu Ke
Published: December 2022

For the vehicle antenna measurement mounting on a vehicle, the offset mounting of the antenna will increase the maximum spherical wave expansion modes, with the increasing calculation time and the increasing risk of introducing environmental reflection noise. Therefore, basing on the matrix form of the traditional spherical wave expansion (TSWE) algorithm, this paper introduces the offset spherical wave expansion (OSWE) algorithm of the offset mounting antenna under test (AUT) aiming to decrease the maximum modes, shorten the calculation time and reduce the environmental noise with the method of spherical wave expansion. Taking LTE antenna and GPS antenna as examples, this paper analyzes the improved performance of OSWE algorithm comparing with TSWE algorithm on the vehicle antenna mounting on a vehicle, as well as the parameters like equivalent noise level (ENL), omnidirectional standard deviation (σ).
Investigation on capacitive force measuring device with linear output
Authors: Zheng Peiliang , Deng Yan , Wang Shuxiang , Wu Dechang
Published: December 2022

Capacitive force measuring device is the most precise of all electrical force force measuring devices with its extremely high sensitivity and resolution. The shape of the capacitive electrode had an important influence on the output of the capacitive force measuring device, and a capacitive force measuring device with linear output could be obtained by regulating the shape of the electrode. The functional conditions that the shape of the capacitor electrode needed to meet when the force measuring device had been linearly output are obtained through theoretical analysis. The output characteristics of two electrode shapes satisfying linear output had been studied through the method of combining theoretical analysis and experiment. Results shown that when the electrode shape satisfied the function condition, the experimental data output of the force measuring device had a good linear relationship, and the linearity could reach more than 0.99. The value of the constant term in the electrode shape function had almost no influence on the output linearity of the force measuring device, but had a direct influence on the slope and intercept of the linear output. For the electrodes with a certain shape, the applied voltage only affected the output range of the force measuring device and did not affect its output linearity. The wide range and high-accuracy measurement of the force measuring device could be realized by using the capacitive force measuring device with linear output with setting different fixed-value loading voltages.
Model-and-data hybrid driven method for power system Operational reliability evaluation with high penetration of renewable energy
Authors: Qi Xiaoguang , Wang Ying , Yu Mingfeng , Wei Zhengze , Zhao Kailin , Chen Yu , Li Xuan
Published: December 2022

With the rising penetration of renewable energy, the fluctuation of operating conditions such as wind speed and light intensity affects the reliability of the power system. It leads to the repeated reliability evaluation of the power systems and increases the computational complexity. Based on the non-sequential Monte Carlo simulation (NMCS) and back propagation neural network (BPNN), a new model-and-data hybrid driven method for power system reliability evaluation is proposed. Firstly, NMCS is used to calculate the system reliability indices under different operating conditions to obtain the input data for neural network training. Then, the proposed Multiple BPNN (M-BPNN) is used to establish the highly nonlinear mapping relationship between operating conditions and system reliability indices, which can significantly reduce the calculation time of power system operational reliability evaluation with high penetration of renewable energy. The IEEE-RTS 79 system is used to verify the effectiveness and efficiency of the proposed method, and sensitivity analysis is performed.
Design and Performance Analysis of an Electromagnetic Railgun
Authors: Du Xiang-yu , Liu Shao-wei , Guan Jiao
Published: December 2022

A railgun is a launcher that accelerates projectiles to super-velocity. In this paper, FEM-BEM coupling simulation method is used to study the electromagnetic characteristics, force and contact state of the railgun and an augmented hyperbolic quadrupole railgun structure is proposed. Compared with the traditional railgun and the non-augmented quadrupole railgun, it is found that the proposed railgun structure has excellent performance in electromagnetic compatibility, thrust on the armature, and the contact state between the armature and the rail. The research of this paper can provide a reference for the structural design of railguns.
Influence of Ridge Groove Structure on Local Field Distribution in Microwave Reaction Cavity
Authors: Zhong Runeng , Li Lin , Yao Bin , Xiang Tai
Published: December 2022

Uneven energy distribution and “hotspot” phenomenon are bottlenecks restricting the development of the microwave heating industry. The formation of high-intensity electric field aggregation areas can be effectively repressed by optimizing the reaction cavity structures. With a box-type microwave reaction cavity as the study object and an external ridge groove as the induction device, the influences of the structural parameters of different devices on the microwave local field distribution were analytically explored through the simulation technology, and a “hotspot” early warning method was proposed. This study provides a reference for inhibiting the “hotspot” phenomenon on microwave fields and optimally designing microwave reactors.
Research and Application of Temperature Load of Switchgear
Authors: Yang Ruibo , Li Tong , Chen Jiehua , Lin Jingfeng , Mao Lei , Wang Mu
Published: December 2022

Abnormal changes in the temperature and load current of the high-current switchgear will directly affect the reliable operation of the equipment. In order to effectively monitor the temperature of the switchgear and ensure the reasonable arrangement of temperature measurement sensors, this paper realizes the optimal arrangement of sensors and the temperature prediction of the switchgear through simulation and test of the switchgear. Firstly, Ansoft electro thermal simulation module is used for joint simulation, the change of temperature field and the heating of current carrying bus are analyzed, the test data of temperature change under different environmental conditions are obtained, and the relationship between the temperature sensor and the distance between the hot spot is mastered. Then the temperature load curves under different currents are obtained through the test, and the accuracy of the research results is verified by the combination of theoretical simulation and field test. The test results can not only provide guidance for the temperature sensor installation scheme of substation field operation and maintenance personnel, but also improve the stability of equipment operation.
Research on improving the reliability of flow measurement of first circuit coolant medium sampling system in nuclear power plant
Authors: Gan Changxian , Wan Tian , Liu Xianbin , Han Hongbao , An Kang , Hu Xiqing
Published: December 2022

The accuracy of flowmeter of the first circuit coolant sampling system in nuclear power plant affects the measurement of the Boron meter. If the fault treatment cannot be completed in time, the reactor state needs to be withdrawn, which will affect nuclear safety and cause great economic losses. In this paper, a feasible improvement scheme is proposed by analyzing the causes of instrument failure, researching the optimization direction, and adopting measures such as seismic analysis, prototype verification, split design, and interference suppression, which effectively improves the reliability of nuclear sampling flow measurement in nuclear power plants.
Study on wind-induced response of corroded transmission tower
Authors: Zhang Li-gang , Ren Yuan , Yao Jian-feng , Tu Zhi-bin
Published: December 2022

Transmission towers in heavily polluted areas and coastal areas are prone to corrosion, resulting in the decline of wind resistance capacity of the structure. In order to study the wind-induced effect of transmission towers under strong corrosive environment, the finite element model of transmission towers with different service life is established by using the corrosion rate model of galvanized coating and the corrosion depth model of steel provided by the specification. The attenuation characteristics of structural natural vibration characteristics are studied, and the variation of displacement, acceleration and stress of tower body under strong wind are analysed. The results show that with the increase of service life, the structural vibration mode changes and the torsional frequency decays fastest, the stress of main members increases gradually. When the service life reaches 50 years, the extreme displacement at tower top and normal stress of member at 95.5 m exceeds limit, making the tower being destroyed.
Study on the pressure fluctuation characteristics of the high-pressure common rail system with a distributor
Authors: Huang Huimin , Tian Bingqi , Geng Liping , Ju Yusheng
Published: December 2022

In allusion to the problem of common rail pressure fluctuation when the high-pressure common rail system (CRS) using double rails, a numerical simulation model of a V-type 8-cylinder engine CRS was established by using AMESim software, and the suppression of pressure fluctuation with and without distributor was studied. The optimum structure dimension of the distributor with length of 100 mm and inner diameter of 9 mm was obtained by uniform design method. Then the pressure surge characteristics of CRS was researched. The research results showed that the installation of the distributor cut down the amplitude of the pressure oscillation of the common rail by more than 62.28%. Therefore, the designed distributor can effectively suppress the rail pressure fluctuation and improve CRS stability.
Analysis of Failure Causes of Grounding Flat Steel for 110kV Transmission Tower
Authors: Fan Pingcheng , Chen Hao , Zheng Jianjun , Yu Xiao , Gong Weiwei
Published: December 2022

The corrosion causes of the grounded flat steel of a 110kV transmission tower were experimentally analyzed by means of macro testing, microstructure inspection, chemical composition analysis, corrosion product morphology and energy spectrum, galvanized layer thickness test, soil physical and chemical property analysis and other test methods. The results show that the improper selection of anti-corrosion process of grounded flat steel and the service environment of alkaline and high salt are the main reasons for its corrosion fracture. It is proposed that the power grid equipment should not use the grounding flat steel of cold galvanizing process, and the inspection of the grounding flat steel of the transmission tower in the Irrigation areas along the Yellow River should be strengthened.
Research on Methods of Increasing Current Carrying Capacity of 110 kV Single Core Cable
Authors: Pang Wei
Published: December 2022

Power cables have been used more frequently in planning and designing the urban power grid. With the rapid development of power grid engineering, the power grid’s capacity is increasing, and the transmission capacity of the cable is also growing. Therefore, it is of great significance to improve the cable carrying capacity. This paper puts forward some methods to enhance the current-carrying capacity of the cable, taking a 110 kV cable as an example, including adopting a reasonable cable arrangement, adopting proper grounding mode and segment length, and reducing the external thermal resistance of the cable and adopting reasonable laying mode. The above methods are calculated and analyzed, and the influence degree of the above methods on the current carrying capacity of the cable is counted, which provides a reference and basis for the design and selection of power cables in the future. Combined with the theoretical calculation and engineering practice of the current carrying capacity of the cable, the cable diameter is reasonably selected, the engineering investment is reduced, and the urban power grid is well constructed to provide a stable power guarantee for urban construction.
Key Technologies for Optimal Design and Stable Cooperative Operation of Broadband Current Array Sensing System
Authors: Fu Dehui , Du Fei , Yu Hao , Yuan Shuai , Chang Wenzhi
Published: December 2022

A new design method of internet of things (IOT) sensor is proposed, various equipment in substation can be abstracted as a complex system composed of directly or indirectly connected equipment nodes, the widely arranged broadband current sensors are used to monitor the current characteristics of high-frequency partial discharge, leakage current and relative dielectric loss of each equipment nodes which are extracted to form a sensor array based on electric flow. System engineering theory is proposed to design the array sensor and is used to optimize layout and operation stability analysis. The designed model and interpretation structure model of IOT sensor system are constructed, based on the state equation or transfer function of the sensor array, the operation stability observation method of the sensor under the missing elements, slight disturbance and severe disturbance is proposed.
Modeling of coordination control system for supercritical unit under wet state operating condition
Authors: Wang Xihui , Chen Houtao , Zhu Xiaoxing , Wang Zhijie , Xun Xin , He Honghao
Published: December 2022

The coordination control system model of supercritical unit under wet state operating condition is established in this paper. Based on the huge historical operating data of a unit, the static parameters and dynamic parameters of the model are solved by data statistics and regression and genetic algorithm and particle swarm optimization algorithm, respectively. Steady-state operating condition points verification, open-loop step response verification, and historical operation data closed-loop verification are conducted. The results show that the model is accurate and can be used for control system designing. For steady-state condition point verification, the relative error between the model output results and the actual data is less than 3.5%. The open-loop step disturbance test can objectively reflect the response characteristics of the unit. As to the closed-loop verification, the relative error between the model output results and the actual data is within 3%.
Vector Proportional Integral Control with Delay Compensation for Stator Excited Doubly Salient Synchronous Motors
Authors: Wu Yihong , Bai Fengxian , Sun Jianzhong
Published: December 2022

This paper proposes a novel current control technique to solve the problem that the special doubly salient structure of the studied stator excitation doubly salient synchronous motor (SEDSSM) causes the motor back EMF to cause large harmonic current and torque ripple. Based on the space vector pulse width modulation sinusoidal drive method, a vector proportional-integral controller with delay compensation (VPIC) is introduced into the current loop to replace the traditional PI controller to control the motor. The SEDSSM stator current under the current loop control mode of conventional PI controller is analyzed, and it is found that its waveform is obviously affected and disturbed by the third harmonic current, which will cause torque pulsation. Therefore, additional resonance items are considered to be introduced into the controller to suppress its harmonic. At the same time, considering that the digital delay in the application of the digital system will lead to an unstable state of the control system under the vector proportional-integral controller, the vector proportional-integral controller with delay compensation is introduced for this purpose. Experimental data tested on a 12/8 SEDSSM prototype show that the VPIC controller can significantly reduce stator current ripple and motor torque ripple compared to the existing PI controller.
Application research on optimal layout of HGIS power distribution devices based on 3D design
Authors: Li Kai , Niu Kai , Zhang Jinfeng , Zhou Zheng , Zhao Chong , Xue Wenjie
Published: December 2022

Taking Shangqiu Yide 220kV outdoor HGIS substation as an example, this paper proposes a optimization design layout set of 220kV HGIS and 110kV HGIS power distribution devices through the application of three-dimensional safety clearance verification, HGIS equipment transportation, installation and hoisting, maintenance, inspection simulation and other three-dimensional technologies.
User-side energy-saving potential assessment method based on non-intrusive load identification technology
Authors: Yao Li , Liu Wei , Lu Chunguang , Xiao Tao , Li Yilong
Published: December 2022

With the development of smart grid, smart meters have been widely used, and the Non-Intrusive Load Monitoring (NILM) technology for sensing and identifying electricity load has gradually matured. Aiming at the problem that the characteristics of industrial users’ load status are few and the gap between different industries is large, this paper uses the random forest algorithm to build a load identification model, and at the same time builds an energy-saving potential evaluation index system including three dimensions of economy, technology and management. Based on the load identification results, users can evaluate the energy-saving potential, and output the use strategies and power consumption suggestions of electric equipment.
Implementation of an Isolated I2C Interface Device Based on OOK Codec
Authors: Feng Jianyu , Yuan Yidong , Zhao Tianting , Yang Xin , Liu Fang , Zhuo Yue
Published: December 2022

As a wide used protocol in industry, BMS and T&D system, I2C bus with isolation features stands out to provide additional safety protection and noise immunity. This paper introduces an implementation method of the isolated I2C interface device with high reliability and low delay. This device can meet the I2C ultra-high speed working mode with communication frequency of 1.7MHz as well as prevent the occurrence of interlock in bi-directional communication. The device is fabricated in 0.18um CMOS process.
Reliable design of communication link for power emergency vehicle mobile station based on Beidou satellite
Authors: Ren Weihe , Yang Yu , Li Zhenqing
Published: December 2022

In order to establish a reliable power emergency communication network and speed up the efficiency of power rescue, a vehicle-mounted reliable communication link based on Beidou short message protocol is designed. Aiming at the unreliability of Beidou short message communication and the limitation of communication capacity, the enhanced data handshake mechanism is adopted to enhance the reliability of data transmission, and the multi-card cooperative transmission mechanism is adopted to improve the efficiency of data transmission. The example results show that the transmission success rate of the proposed reliable communication link is significantly higher than that of the traditional method, which can improve the reliability of mobile station data transmission and provide communication guarantee for power recovery.