bluuebunny/crossref_metadata_2025 huggingface dataset:
Sektorgrenzen überwinden: Einkaufs- versus Sachkostencontrolling im Krankenhaus – zwei Seiten derselben Medaille?
Authors: Herbst Vanessa
Published: November 2021

Einkaufs- und Sachkostencontrolling ist hochkomplex. Nur durch interdisziplinäre Begleitung des Klinikeinkaufs, Medizincontrollings und den Anwendern kann die Unternehmensführung nachhaltige Entscheidungen treffen.
Essenslogistik in der Krankenhausverpflegung: Speis und Trank für Leib und Seele
Authors: Kriegel Johannes
Published: November 2021

Die Speisenversorgung gewinnt im Rahmen der stationären Patientenversorgung zunehmend an Bedeutung. Logistische Gestaltungsansätze bilden auch hier die Möglichkeit, Servicepotenziale zu heben, Ressourceneffizienzen zu erschließen sowie die patientenindividuelle Versorgungsqualität zu verbessern.
Klinikeinkauf im Wandel: Value-based Healthcare & Value-based Procurement: Hintergründe und Ideen
Authors: Gallmann Thomas
Published: November 2021

Value-based Procurement hält zunehmend Einzug in die Welt der europäischen Beschaffung. Der Klinikeinkauf kann damit die Rolle eines Wertketten-Integrators übernehmen.
Frequency fluctuations of ferromagnetic resonances at millikelvin temperatures
Authors: Wolz Tim , McLellan Luke , Schneider Andre , Stehli Alexander , Brehm Jan David , Rotzinger Hannes , Ustinov Alexey V. , Weides Martin
Published: November 2021

Unwanted fluctuations over time, in short, noise, are usually detrimental to device performance, especially for quantum coherent circuits. Recent efforts have demonstrated routes to utilizing magnon systems for quantum technologies by interfacing single magnons with superconducting qubits. However, the coupling of several components often introduces additional noise to the system, hence degrading its coherence. Researching the system's temporal behavior can help us to identify the underlying noise sources, which is a vital step toward improving coherence times and hybrid device performance. Yet, the frequency noise of the ferromagnetic resonance (FMR) has so far been unexplored at mK-temperatures. Here, we investigate such FMR frequency fluctuations of a yttrium-iron-garnet (YIG) sphere and find that these fluctuations are independent of temperature and drive power. This suggests that the measured frequency noise in YIG is dominated by undetermined noise sources, whose properties are not consistent with the conventional model of two-level systems, despite their effect on the sample linewidth. Moreover, the functional form of the FMR frequency noise power spectral density (PSD) cannot be described by a simple power law. By employing time-series analysis, we find a closed function for the PSD that fits the observations. Our results underline the necessity of coherence improvements to magnon systems for useful applications in quantum magnonics.
Compact acoustic monolayered metadecoder for efficient and flexible orbital angular momentum demultiplexing
Authors: Liu Jing-Jing , Ding Yu-Jiang , Wu Kai , Liang Bin , Cheng Jian-Chun
Published: November 2021

Detecting the orders of an orbital angular momentum (OAM)-carrying beam is of fundamental interest and practical importance in wave physics. Yet accurate and fast demultiplexing of free-space OAM beams within physical space comparable to wavelength still remains challenging. Here, a passive monolayered metadecoder with compactness, high efficiency and flexibility is designed systematically and demonstrated experimentally for real-time demultiplexing of multiple OAM modes in free space. A simple yet effective mechanism of simultaneously untwisting and reshaping the synthesized vortex beams is presented to remarkably downsize the device and arbitrarily modulate the propagation path of output beam with amplified intensity and intact information, whose detection needs no sensor array or postprocessing. Consequently, the resulting device features the ultra-compact size, enhanced signal-to-noise ratio, high spectral and spatial selectivity, controllable detection locations, and furthermore, the compatibility to existing multiplexing methods. The effectiveness of proposed mechanism is demonstrated numerically and experimentally via parallel and real-time demultiplexing of a synthesized acoustic vortex using a planar metadecoder much more compact than existing devices in all three dimensions. The realization of metadecoder offers the possibility of high-capacity and miniaturized passive devices harnessing OAM and may promise important applications, including advances in high-speed underwater communication and optical on-chip signal process.
Role of magnetocrystalline anisotropy on anisotropic magnetocaloric effect in single crystals
Authors: Zhang Jiayu , Hu Yong
Published: November 2021

The role of magnetocrystalline anisotropy in single crystals played on the anisotropic magnetocaloric effect is studied based on Monte Carlo simulation. By taking into account the anisotropy, the spin reorientation transition (SRT) temperature (TSRT) may be higher than the Curie temperature and enhanced with larger anisotropy, and the magnetization behaviors at low temperatures below TSRT and under weak fields are highly sensitive to the anisotropy. The anisotropy of entropy change is the most significant when the magnetic field is parallel to the easy axis, while the maximum entropy change may increase or decrease with the anisotropy constant in a given direction depending on the magnetic field strength. Power-law fits have been conducted on the field dependence of the maximum entropy change and relative cooling power, which not only indicate a characteristic of the second-order phase transition but also demonstrate effect of anisotropy on magnetic order and dynamics during the SRT to contribute to the anisotropic magnetocaloric effect.
Enhancement of electromagnetically induced transparency based Rydberg-atom electrometry through population repumping
Authors: Prajapati Nikunjkumar , Robinson Amy K. , Berweger Samuel , Simons Matthew T. , Artusio-Glimpse Alexandra B. , Holloway Christopher L.
Published: November 2021

We demonstrate improved sensitivity of Rydberg electrometry based on electromagnetically induced transparency (EIT) with a ground state repumping laser. Though there are many factors that limit the sensitivity of radio frequency field measurements, we show that repumping can enhance the interaction strength while avoiding additional Doppler or power broadening. Through this method, we nearly double the EIT amplitude without an increase in the width of the peak. A similar increase in amplitude without the repumping field is not possible through simple optimization. We also establish that one of the key limits to detection is the photon shot noise of the probe laser. We show an improvement on the sensitivity of the device by a factor of nearly 2 in the presence of the repump field.
Comparing GIPAW with numerically exact chemical shieldings: The role of two-center contributions to the induced current
Authors: de Wijs Gilles A. , Kresse Georg , Havenith Remco W. A. , Marsman Martijn
Published: November 2021

In this study, we benchmark density functional theory gauge-including projector-augmented-wave (GIPAW) chemical shieldings against molecular shieldings for which basis set completeness has been achieved [Jensen et al., Phys. Chem. Chem. Phys. 18, 21145 (2016)]. We demonstrate the importance of two-center corrections for GIPAW hydrogen shieldings. For the other nuclei studied, standard GIPAW is sufficiently accurate. We find that GIPAW can be pushed to closely approach the basis set limit. The only source of small inaccuracies lies in the contribution to the shielding that is caused by surface currents, which we estimate comparing GIPAW susceptibilities to converged molecular magnetizabilities.
Raman frequencies of diamond under non-hydrostatic pressure
Authors: Mohammed Idris Bakhit Alaa , Mutisya S. , Scandolo S.
Published: November 2021

The Raman frequencies of diamond subjected to non-hydrostatic uniaxial stress along the [001] and [111] crystallographic axes have been calculated with density-functional-theory methods and the results fitted to a simple analytical form. The data are analyzed in the context of the recently proposed use of the shift of the high-frequency edge of the Raman band of diamond as a pressure scale in diamond-anvil cell experiments. Combining theoretical and experimental data, we are able to determine the stress state of the diamond anvil in ultra-high-pressure experiments. We find that shear stresses close to the tip of the anvil can reach values exceeding 1 Mbar.
Joint creative process in translation
Authors: Korhonen Annamari , Hirvonen Maija
Published: November 2021

In this article, we explore socially distributed cognition (SDC) as a theoretical model of translation and investigate it empirically as an aspect of the collaborative and creative translation workflow. With the aim of developing a better understanding of SDC and collaborative workflows in translation, we analyzed two different settings where more than one person works on a translation: commercial specialized translation (CST) services, and the production of audio descriptions (AD) as teamwork between blind and sighted describers. The analysis focuses on how the process of co-creation unfolds in the communication that binds together the systems of SDC. While the process of co-creation was strikingly similar in the two different translation contexts, the differences were bound to channels of communication (with or without direct contact between participants), and the draft translation was identified as a central artifact that carries much of the communication when the participants do not work in the same space. With an emphasis on socially distributed cognition, our study provides a framework for both the cognitive and social aspects of translation and develops the understanding of collaborative translation processes. It also contributes to the development of translation practices by helping translation operators and trainers make choices between alternative workflows.
Translation teams as cognitive systems
Authors: Pleijel Richard
Published: November 2021

This paper aims to bring research on different forms of group-level cognition into conversation with Cognitive Translation Studies (CTS), the focal point of the paper being cognitive processes in translation teams. It is argued that an analysis of cognition in translation teams, which exhibit the properties of a cognitive system, needs to be placed on group-level. A case study of a team, translating the Hebrew Bible Book of Psalms into Swedish in the 1980’s, is presented. The empirical base for the case study consists of archival material in the form of draft translations and paratexts. The methodological question is thus raised whether, and if so in what way, cognitive processes may be analyzed retrospectively, and not only from a real time perspective. By treating the archival material as cognitive artifacts which have constituted an integral part of the team’s cognitive process, the question is tentatively answered in a favourable way. This, it is finally argued, opens up interesting possibilities for joining CTS with translator archives research, Genetic Translation Studies (GTS), and cognitive archeology.
Gesture development in Peruvianchildren and its relationship with vocalizations and vocabulary
Authors: Fernández-Flecha María , Blume María , Junyent Andrea , Tijero Neyra Talía
Published: November 2021

We examine gestural development, and correlations between gesture types, vocalizations and vocabulary at ages 8 to
15 months, employing data from MacArthur-Bates Communicative Development Inventories for Peruvian Spanish, in the
first such study with Peruvian children. Results show (1) significant change with age in the production of gesture types, with
older children producing more; (2) important correlations between gesture types, and both vocalization types and vocabulary after
controlling for age effects; and (3) correlations between the trajectory of the pointing gesture in its two modalities (whole-hand
and index-finger) with age, vocalizations, and vocabulary, an effect that persists with respect to vocalizations after controlling
for age. Our findings, based on a sample from a non-weird population, support a key role for gesture production in early
communicative and linguistic development.
Gaze selects the next speaker in answers to questions pronominally addressed to more than one co-participant
Authors: Auer Peter
Published: November 2021

Like many other languages, but unlike modern (standard) English, German has a distinct second person plural pronoun (ihr, ‘you guys’), contrasting with the second person singular pronoun (du). The second person plural pronoun addresses a turn to more than one, and possibly all co-present participants. This paper investigates turn-taking after such multiply addressed turns, taking as an example information-seeking questions, i.e., a sequential context in which a specific next action is relevant in the adjacent position. It might appear that in such a context, self-selection applies (Schegloff 1992: 122); more than one co-participant is addressed, but none selected as next speaker. In this paper, I show on the basis of spontaneous interactions recorded with mobile eye-tracking equipment that this is not the case and that TCU-final gaze is employed to select the next speaker. The participant not being gazed at TCU-finally is addressed, but not selected as the answerer in next position and may provide an answer in a sequential position after the first answer. The article demonstrates that gaze is an efficient way to allocate turns in the absence of verbal cues and thus contributes to our understanding of turn-taking from a multimodal perspective.
From translation zone to sacrifice zone
Authors: Cronin Michael
Published: November 2021

One of the most extreme challenges facing humanity at present is the climate crisis. Responding appropriately to this crisis requires a fundamental re-examination of received ways of thinking about translation, among other things. Contrasting the eco-minor with the eco-major mode of representing ecological crisis, we argue for the importance of minority perspectives in developing an expanded remit for translation studies in the context of the climate emergency. The concepts of relational and situational minority are advanced to explore how indigenous translation hermeneutics can inform climate debates. In line with environmental debates around the importance of ‘thinking outdoors’, we advocate for a notion of ‘translating outdoors’ and seek to incorporate this line of enquiry into the development of the concept of the city as more-than-human translation zone. In the coming age of extreme climate conditions, no socially responsible understanding of translation can afford to ignore ecological perspectives on the practice.
Creep behaviour of different microstructural zones of TIG-welded semisolid cast AXE622 alloy
Authors: Eftekhar A. Habibi , Mohsen Sadrossadat S. , Reihanian M.
Published: November 2021

The impression creep behaviour of a TIG-welded semisolid cast AXE622 Mg alloy is investigated at the temperature range of 423–498 K and the stress range of 450–600 MPa. After creep, the (Mg–Al)2Ca phase loses its continuity in the HAZ, and some evidence of particle fracture is obvious. Except at 423 K, where the HAZ exhibits a higher creep resistance than in the FZ, the creep resistance decreases from BM to FZ. The power-law break dawn is the rate-controlling creep in BM though the dislocation creep is dominant in HAZ and FZ. Moreover, the creep is controlled by pipe diffusion in BM while a dislocation nucleation mechanism at the boundary surface is activated in the HAZ and FZ.
CP-violating transport theory for electroweak baryogenesis with thermal corrections
Authors: Kainulainen Kimmo
Published: November 2021

We derive CP-violating transport equations for fermions for electroweak baryogenesis from the CTP-formalism including thermal corrections at the one-loop level. We consider both the VEV-insertion approximation (VIA) and the semiclassical (SC) formalism. We show that the VIA-method is based on an assumption that leads to an ill-defined source term containing a pinch singularity, whose regularisation by thermal effects leads to ambiguities including spurious ultraviolet and infrared divergences.
We then carefully review the derivation of the semiclassical formalism and extend it to include thermal corrections. We present the semiclassical Boltzmann equations for thermal WKB-quasiparticles with source terms up to the second order in gradients that contain both dispersive and finite width corrections. We also show that the SC-method reproduces the current divergence equations and that a correct implementation of the Fick's law captures the semiclassical source term even with conserved total current ∂μ
j
μ = 0. Our results show that the VIA-source term is not just ambiguous, but that it does not exist. Finally, we show that the collisional source terms reported earlier in the semiclassical
literature are also spurious, and vanish in a consistent calculation.
On the Trans-Planckian Censorship Conjecture and the generalized non-minimal coupling
Authors: Guleryuz Omer
Published: November 2021

We investigate the Trans-Planckian Censorship Conjecture (TCC) and the arising bounds on the inflationary cosmology caused by that conjecture. In that investigation, we analyze TCC bounds for both Jordan and Einstein frames in the presence of a generic non-minimal coupling (to gravity) term. That term allows us to use the functional freedom it brings to the inflationary Lagrangian as an effective Planck mass. In this sense, we argue one should consider the initial field value of the effective Planck mass for the TCC. We show that as a result, one can remove the TCC upper bounds without the need to produce a new process or go beyond the standard inflation mechanism, with the generalized non-minimal coupling, and for Higgs-like symmetry-breaking potentials.
Comparison of Fuel Cell DC/DC Power Supply Topologies
Authors: Chen Guofu , Dai Fengjiao , Kang Wei
Published: November 2021

With the development of fuel cell products and technology, power electronics researchers have proposed a variety of fuel cell DC/DC power supply topologies for the output characteristics of fuel cells. This article compares and analyzes several existing non-isolated and isolated topological structures, summarizes the respective advantages and disadvantages of different topological structures and applicable scenarios, and provides references for further indepth discussion of related issues.
Research on Rates Discharge Characteristics of High Energy Density Ternary Lithium Battery
Authors: Lu Changbo , Sun Yanli , Zhang Chunlin , Zhou Lijie , Chen Jinmao
Published: November 2021

In order to study the effect of rates discharge on characteristics of ternary lithium batteries, a new type of high rate ternary lithium battery from a unit is used as the research object. The discharge test is carried out at the discharge rates of 1C, 4C, 7C, 12C and 15C on this ternary lithium battery at room temperature with high and low temperature charge/discharge test system. The test results show that the energy density under 1C rate discharge is 202.62wh/kg. Correspondingly, the energy density under 4C, 7C and 12C rate discharge is 95.17%, 93.83% and 91.79% of the value under 1C rate discharge respectively. Even for 15C rate discharge, its energy density can reach 87.15% of 1C rate discharge. During the discharge process, the temperature of the battery increased with the increase of discharge rate, and the temperature rise at 15C rate by 26 °C.
A Current Amplifier Circuit and Control Strategy Based on FPGA
Authors: Gu Wei , Zhang Lihui , Xie Junkai , Shi Guangnan , Zhang Haibo , Yu Quanqing , Zhu Honglin
Published: November 2021

With the extensive application of electric vehicles, energy storage systems and other power electronic equipment, the research on large capacity controllable current source will be an important direction in the future. This paper proposes controllable current source controlled by a full digitally hysteresis current based on field programmable gate array(FPGA), in which the single phase full bridge topology is adopted as the main circuit of current source. The two levels and three levels hysteresis current control strategies are analyzed and compared with the platform of PSCAD/EMTDC. The user defined component was adopted to realize the two difference control strategies with fortran language program. The simulation results verified that the two levels hysteresis current control strategy is much more fit for the controllable current source. Finally, a prototype is designed and fulfilled and it is controlled by the digitally controller with FPGA. The hysteresis current control is realized by FPGA controller with VHDL programming. The experimental results show that the researched hysteresis current control technology is effective for the current amplifier
Research on the Calculation Method of Distributed Photovoltaic Access Capacity Considering Harmonic Characteristics
Authors: Su Junhu , Yang Zhaoguang , Liu Xu , Yang Jingyu , Jiang Minghua
Published: November 2021

To raise the maximum access ability of the maximal distributed photovoltaic system, based on the metering terminal of plant and station system for many years, a nonparametric estimation method based on kernel density is proposed to calculate harmonic probability distribution, this paper proposes the calculation method of superposition index and simultaneous coefficient suitable for distributed photovoltaic grid-connection, and puts forward the capacity calculation method considering harmonic constraints. An example shows that the proposed method can increase the maximum admittance capacity by at least 15% compared with the traditional method under the condition that the harmonic emission level does not exceed the threshold value of national standard, and realize the safe, stable and economic operation.
Research and Application of Power System Data Anomaly Identification Based on Time Series and Deep Learning
Authors: Li Chao , Li Xiaolei , Liu Xingyu , Zhao Lin , Xiao Dajun , Hao Xuliang , Xie Jun , Xu Xialing
Published: November 2021

Abnormal data in the power system will reduce the accuracy of system state estimation and affect the safe operation of the power dispatch system. This paper proposes a data anomaly identification model based on time series and neural network, which establishes time series for various measuring points of the control master station, creates a time series group of associated measuring points based on the network topology, and extracts the sample characteristics of the time series. The neural network model is used to realize the intelligent identification of normal data and abnormal data. The neural network recognition results are compared with normal distribution and DBSCAN density clustering methods to verify the abnormal recognition performance of the neural network. Using a provincial power grid dispatch center operating data set as a training and testing sample, it verifies the advancement of the proposed method in the comprehensive performance of anomaly detection recall rate and precision rate and its feasibility in actual system application.
Research on Intelligent Operation and Maintenance Model of Large Database for Electric Power Industry
Authors: Yang Chaoyi , Liu Ye , Xiao Jianyi , Huang Xiaobo , Chen Jiahua
Published: November 2021

Existing research on automated database operation and maintenance for the electrical industry mainly focuses on distributed and cloud platforms, and there is a lack of traditional large-scale database intelligent operation and maintenance research. This paper designs an overall operation and maintenance model framework of “intelligent perception-intelligent decision-intelligent execution”, and proposes feasible implementation plans, including: (1) Use the prophet time series forecasting model to perceive and predict important database performance indicators, and dynamically adjust the threshold of each performance indicator according to the predicted value; (2) Perform correlation analysis on abnormal indicators through the association rule model to construct “Indicators”->Operation” optimized combination operation strategy library for intelligent decision making; (3) According to the intelligent decision library, automatically restrict the associated operations under abnormal conditions to ensure the normal operation of the service and realize intelligent execution.
A Clustering Routing Algorithm for Wireless Sensor Monitoring Network in Irrigation Area
Authors: Li Lianguo , Ren Kang , Fan Tanghuai , Shen Keyong , Hu Rongqun
Published: November 2021

It is the basis for the implementation and scientific management decision of precision irrigation to accurately and comprehensively sense water and rainfall regime, soil moisture content and engineering conditions in irrigation areas and various environmental factors closely related to crop growth. In view of the characteristics of large monitoring range and scattered distribution of measuring points in the irrigation area, based on the analysis of the characteristics of the strip shape layout of the wireless sensor network at the water demand side of the irrigation area, and the limited battery energy and transmission distance under the condition of battery power supply, a clustering routing algorithm based on wireless sensor network for monitoring irrigation area is proposed (known simply as CRAIM algorithm). The formation of clusters, the selection of cluster heads, the routing process between clusters and the sink nodes are studied, and the CRAIM algorithm, EE-LEACH (energy-efficient LEACH) and MMH-LEACH (modified multi-hop LEACH) algorithm are simulated and compared respectively. Experimental results showed that, the new algorithm, CRAIM, has some advantages in the energy consumption of the network.
Research on Highway Slope Disaster Automated Monitoring Method Based on Video Image Processing
Authors: Zhang Zhuomin , He Song , He Chaonan , Chen Yi , Shi Haobo
Published: November 2021

With the rapid development of China highway transportation network, a lot of highways have risen in the mountainous areas. And the risk of geological disasters is also increasing. Due to the instability of the geological structure and geological changes, slope landslides and collapses frequently occur. However, there is a lack of effective means and tools in the field of highway slope disaster monitoring. For large and important slopes, various information-based monitoring methods are used, but the effects and practicability are not satisfactory. This paper proposes a highway slope disaster automated monitoring research method based on multi-camera video image processing to solve the previous engineering problems of slope video monitoring. It can quickly identify slope disaster events with centimeter-level monitoring accuracy, which can meet the application requirements of highway engineering. Correspondingly, the disaster emergency response capabilities of highway operators can also be supported and improved.
Analysis of an Automatic Early Warning System Based on Fog Architecture
Authors: Shi Gang , Yang Yuechen
Published: November 2021

In the process of analysing and processing terminal sensor information, a large number of terminal sensors are needed to collect front-end information. These front-end data collection, analysis and processing require high real-time, and need the support of location aware mobile computing services. Traditional cloud computing architecture is not the best choice for service scenarios with high real-time requirements. The fog computing architecture is to extend cloud computing services to the edge of the sensor network, coupled with appropriate fitness algorithms, can effectively improve the information analysis and early warning response speed of the geological disaster information early warning system.
Human Recognition Using Joint Coordinate Images (JCIs) with Convolutional Neural Network
Authors: Kong Deyu , Zhang Xuejun , Wei Yini , Xu Xianfu , Zeng Hongjie , Li Bin
Published: November 2021

Human recognition with skeletal data has the advantage in detecting people without their face characteristic on image. However, the accuracy of recognition by this method is always low because it relies deeply on manual feature selection. We propose a novel human recognition method called Joint Coordinate Images (JCIs) with Convolutional Neural Network (CNN) based on the image generated from skeletal information tracked by KinectV1. In order to represent human physical skeletal characteristic, the coordinate values XYZ of human joint tracked by KinectV1 are firstly created in color image called Joint Coordinate Images (JCIs), in which the relative position of the pixels represents the skeletal structure characteristics of participants with shape in “大” structure. Secondly, a new convolution neural network classifier Lenet-5 model, which always performed well in image classification, was modified to be able to input our JCIs for human recognition. The experimental results show that human recognition using joint coordinate image and Lenet-5 network can reach the highest recognition accuracy of 90.00% on the G3D dataset, which demonstrates the feasibility to transform the skeletal coordinate information into color image for human recognition task and could be used as a complementary method to the well-known application of face recognition.
Research and Application of Flutter Suppression Technology for Aeroengine Case Machining
Authors: Xiao Yang , Liu Bo , Wei Jie , Xiao Chenfan , Li Tian , Li Xiaowei
Published: November 2021

The magazine is an important part of the aero-engine, its main role is to bear the load and mass inertia force generated by the engine in the work. The design and manufacturing level of the magazine is of great significance to improve the aero-engine’s quality. Engine magazine belongs to a thin-wall cylinder part with large size, complex shape and high processing precision. Due to its thin wall rigidity difference, the processing quality is easy to reduce caused by the vibration of machine tools and other processing system, and cannot meet the requirements. According to the absorption principle of TMD (Tuning Mass Damper), an auxiliary fixture is designed to transfer the magazine processing vibration energy to the auxiliary fixture to reduce the vibration of the processing system and to improve the processing quality. Through ANSYS analysis, the maximum vibration amplitude of the magazine was reduced by 60% by using this fixture. Therefore, the fixture can significantly reduce the vibration in the processing and have good effect on improving the quality of the processing. The auxiliary fixture has the advantages of simple installation, simple disassembly, and strong scalability.
Research on a New Type of Lattice Roller Frame
Authors: Feng Baozhong , Lan Chunsen
Published: November 2021

In view of the structural defects of the current belt conveyor roller frame, such as heavy weight and high labor intensity of disassembly and assembly, a new lattice roller frame was designed by changing the structure and profile. On the premise of meeting the work conditions, the weight of the roller frame was reduced by more than 45%, which not only reduced the labor intensity of disassembly and assembly, but also reduced the tonnage and cost of consumables of the belt conveyor, and it has a broad market prospect.
Design and Validation of Thermal Insulation for Deep-sea Fluid Sampler of Jiaolong Human Occupied Vehicle
Authors: Yu Kaiben , Zong Le , Yu Shengqi , Meng Qingjian , Liu Baohua
Published: November 2021

In this paper, a thermal insulation structure with silica aerogel felt as filler material was designed for the requirements of deep-sea fluid thermal insulation sampling technology for Jiaolong human occupied vehicle. Simulation analysis of thermal insulation performance was carried out and an experimental prototype was developed for the thermal insulation structure. Experimental study on thermal insulation performance was conducted with the variation characteristics of the operation environment for Jiaolong human occupied vehicle being taken into account. Results show that the silica aerogel felt with a thickness of 30 mm filled in the radial space between the inner and outer cylinders can achieve the expected thermal insulation effect during the diving-sampling-transferring process, with maximum temperature rise of 8.5 °C, and can meet the requirements of deep-sea fluid thermal insulation sampling technology.
A Nuclide Recognition Method for Nuclear Robot System
Authors: Zhou Siyi , Zhang Jiangmei , Feng Xinghua , Zhang Caolin
Published: November 2021

In the real energy spectrum attenuation environment, many traditional nuclide identification methods for nuclear robot systems have problems such as using only part of the energy spectrum curve, being susceptible to noise, and having low recognition accuracy. Proposes an energy spectrum nuclide recognition method based on S-transform (ST) and Mahalanobis distance-based support vector machine (MSVM). Regarding the energy spectrum curve as a non-stationary signal, combined with the widely used S transformation method in signal transformation, the energy spectrum data is two-dimensional, Then use two-dimensional principal component analysis(2D-PCA) to reduce the dimension of the two-dimensional energy spectrum data for feature extraction, and design a support vector machine (SVM) classifier based on Mahalanobis distance to realize the identification of energy spectrum nuclides. Finally, experiments are carried out with simulated nuclide energy spectrum data based on Geant4. The experimental results show that this method effectively improves the accuracy of energy spectrum nuclide recognition by using full spectrum information. At the same time, experiments are carried out on the nuclide energy spectrum data of different detection distances obtained by the NaI detector in the real environment, and it is verified that the algorithm proposed in this paper also has a good recognition performance for the nuclide energy spectrum collected in the real environment.
Research on Quantitative Analysis Method of Combined Maintenance Task
Authors: Yu Na , Zhang Tao
Published: November 2021

In this paper, the delay time theory is used to establish the mathematical model of the combination of monitoring and periodic replacement tasks, and the impact of maintenance period of monitoring and periodic replacement is discussed. Through the optimization solution, the optimal cycle of combined maintenance tasks is obtained to minimize the maintenance cost while ensuring the reliability. Finally, an example is given to demonstrate the feasibility of this method.
Research on Collision Detection Method of Contact On-line Measurement
Authors: Qi Hongfang , Guo Runqi
Published: November 2021

In order to avoid collision and improve the safety of on-line measurement, a contact on-line measurement collision detection method is studied. Firstly, according to the structural characteristics of the probe and workpiece, the dynamic collision detection between the probe and workpiece is transformed into static collision detection by using the discrete method, and then the grid division of the collision detection space is carried out by using the space division method. Finally, the dynamic collision detection between the probe and workpiece is transformed into the intersection judgment between simple geometry, and according to different collision accuracy requirements, Hierarchical collision detection combining rough detection and fine detection is carried out. Experimental results show that the hierarchical collision detection algorithm has high detection speed and accuracy.
Quantum Key Distribution by Drone
Authors: Wang Z. , Guo Z. , Mogos G. , Gao Z.
Published: November 2021

A cryptographic communication system is secure from a practical point of view if the encryption scheme can be broken after X years, where X is determined by security needs and existing technology. Quantum cryptography does not offer a complete solution for all cryptographic problems: secure keys, encryption algorithms based on them, message authentication and finding ways to detect/prevent interception; but it can be seen as a complement to standard symmetric cryptographic systems. This paper presents the implementation of the BB84 quantum key distribution protocol on mobile systems - Amov-lab’s Z410 drone with T-engine 2216 - and tracks the error rate obtained in flight conditions.
Optimization of Low Frequency Acoustic Absorption Characteristics of Underwater Acoustic Cover Based on Nelder-Mead Simplex Method
Authors: Wang Jiabei , Zhou Hao
Published: November 2021

In order to solve the low frequency sound absorption problem of acoustic covering layer, the local resonant cavity covering layer is established. The geometric parameters and material parameters of the composite structure are taken as optimization variables, the maximum sound absorption coefficient in the frequency band of 10-2000Hz is taken as optimization objective, and the Nelder-Mead simplicated method was used as optimization method to optimize the established model. The optimization results show that the sound absorption coefficient of the composite structure is increased by 13% and 24% respectively after the optimization of geometric parameters and material parameters. The sound pressure level of the sound wave emitted into the water area is reduced by about 3dB after the optimization, and the power loss is equivalent to increasing by half. Therefore, the sound absorption performance is improved. The research results can provide a theoretical basis for the design of acoustic coating.
Effects of X Rudder Area on the Horizontal Mechanical Properties and Wake Flow Field of Submarines
Authors: Xiao Xiao , Liang Qiufeng , Ke Lin , Hu Yi , Zhang Lu
Published: November 2021

X rudder is particularly important for submarine maneuverability, but its influence on wake flow field remains largely unknown. In this study, the X rudder was scaled down three-dimensionally to 80%, 85%, 90%, 95% and 100% of the original rudder area with unchanged aspect ratio and installation position of rudder shaft. Next, the effects of X rudder area on the horizontal mechanical properties and wake flow field of the submarine with a tail control plane were analyzed using the CFD method. The results showed that when the X rudder area was reduced by 20%, the resistance was not significantly affected, and the yaw torque was still larger than that of cross-shaped rudder submarine. At the rudder angles of 0°, 2° and 5°, the velocity non-uniformity coefficients of S1 were reduced by about 9%, 25% and 71%, respectively, when compared to those of S5.
An Adhesive Wear Model Based on a Complete Contact Model for a Fractal Surface
Authors: Li Xin , Wang Bingbing
Published: November 2021

An adhesive wear model based on a complete contact model for a fractal surface is presented in this work. A contact model which contains effect of adhesion is firstly presented based on ME model. A complete contact model is then proposed. Finally, an adhesive wear model based on this model is given. The results suggest that the maximum contact area increases firstly and then decreases as fractal dimension increases. The percentage of plastic contact area increases with increase of the fractal dimension. And the experimental results for wear volume have shown a good consistency with the results calculated by the wear model.
Structural analysis of non-standard geometric variants of a shifted spur gear
Authors: Konecki K , Wojtkowiak D , Talaśka K , Kołodziej A , Domek G
Published: November 2021

Today's industrial practice shows that - in contrast to the past years, where gears were designed as standard as possible - machine parts are constructed on the basis of selecting non-standard parameters. This is because producers protect themselves against making additional parts from local suppliers for much less money by customers. The paper presents a geometric and strength analysis of an exemplary spur gear, which works as the second stage of a bevel-helical gear in the coiling mechanism of a multi-module machine producing bonell springs for mattresses. It was checked whether the transmission could be redesigned in such a way as to make its geometry as complicated as possible while maintaining the appropriate strength properties. Finally, there are graphs that can be helpful in this type of reconstruction process, and the subsequent stages of this work can be treated as a kind of algorithm for the discussed conversion of geometric parameters of the gear.
Experimental verification of high-strength composite materials using a simulation program
Authors: Knapčíková L , Husár J , Kaščak J
Published: November 2021

The use of composites in engineering applications has been steadily growing in recent years. Despite this growth and despite some important advantages of the properties that composites offer, such as reduced weight, design freedom, etc., a breakthrough in high- volume components in engineering applications has not been achieved at present. Therefore, when designing selected parts and structures using new materials, such as composites, material and manufacturing costs must be considered a high priority if further significant growth is achieved. However, many other factors must also be considered when designing a composite part for engineering use. These factors also depend on the particular material or combination of materials being evaluated. The paper is focused on testing a composite material manufactured from polybutylene terephthalate (PBT), reinforced with high-strength fibres Cordenka and Aramid fibres. The composite material's mechanical properties were verified using Ansys simulation software.
Gear shape optimization for non-circular gearing
Authors: Maláková S , Sivák S
Published: November 2021

The quality of gearings is largely decided by their geometric design. If the geometric design is incorrect, the reliability of the transmission will not be ensured even by the use of the highest quality materials. Conversely, sometimes excellent geometric gear design can save expensive material costs. The work describes the procedure of optimizing the geometric model of a non-standard elliptical gear eccentrically mounted with a continuously changing gear number for specific parameters.
Thermal and Mechanical Characterization of Drawn Polypropylene Fibres
Authors: Krmelová V , Gavendová M , Krmela J , Skalková P , Loksik E
Published: November 2021

The main objective of this work was to investigate the effect of different cellulose (CEL) content and the draw ratio on the thermal and mechanical properties of drawn polypropylene (PP) fibres. The modification of PP fibres during their production can helps to prepare PP fibres with improved properties, guarantees new opportunities for the expansion of an assortment of PP fibres in the clothing and domestic textile industries. The modified PP/CEL fibres were prepared from PP pellets and PP/cellulose masterbatch via the melt spinning technique at 260 °C followed by drawing for various draw ratios in the company Chemosvit, Fibrochem a. s. (Svit, Slovakia). Differential scanning calorimetry (DSC) was used to evaluate the thermal properties of PP fibres. The mechanical properties (tenacity and elongation at break and modulus of elasticity) and low cycle loading of modified PP fibres were also studied. The obtained experimental results of drawn PP/CEL fibres were compared with neat PP fibre prepared under the same technological conditions. Cellulose had a minimal effect on the melting temperatures of fibres and increased of the PP crystallization temperatures in comparison with the neat drawn PP fibre. The limited decrease of mechanical properties of prepared fibres were observed, but the decreases do not influence on the fibres commercial use.
Technical solution of the modern conveyor system
Authors: Jakubovičová L , Kopas P , Vaško M , Handrik M
Published: November 2021

The modern conveyor system finds its place in industrial automation. It offers a full and diverse range of custom conveyor solutions and types. Aluminium profiles offer huge range of different sizes. Conveyors are useful to move materials and smooth transfer along the tracks. Therefore, this paper aimed to designed conveyor system using by aluminium profiles. The aim of the paper is to point out the issue of modularity of our designed conveyor system through design and technological parameters that directly affect its use for the needs of practice. They can be installed almost anywhere, and they transport loads of all shapes, sizes and weights.
Design and selection of a belt drive for an electric generator
Authors: Dudziak M , Domek G
Published: November 2021

The issue of the selection of mechanical drive for medium size power generators was raised in the work. The issue begins with the analysis of the propulsion system in the hydroelectric power plant, in which the turbines were selected for the amount of water flowing and for these turbines electric generators. An overview of the available drive solutions pointed to belt transmissions, which must meet the task of transferring torque from the turbine to the generator. The solution must be durable, which is why the authors conducted a deep analysis of material issues and pointed to modern polymer strips that can meet the challenges posed.
Modern trends in the development of electrical discharge machining
Authors: Kuchta P , Straka Ľ , Zajac J , Radchenko S
Published: November 2021

The current time is characterized by the rapid development of modern production methods. These modern production methods are in many cases closely linked to progressive production methods, including EDM. The required high productivity and product quality is the reason for using such production methods. In addition to flawless production processes and highly sophisticated production equipment, these requirements can only be met using high-quality production tools. This paper, therefore, aims to describe the results of the analysis of current approaches in the field of modern trends in the development of electrical discharge machining, closely focusing on the development of control systems for generating electrical impulses in connection with the development of advanced tool electrodes. The performed analysis is also supplemented by the definition of mutual relations between selected properties of wire tool electrodes, their cutting power, and the achieved quality of the machined surface after electrical discharge machining. This should significantly help in increasing the quality level of the machined surface during wire electrical discharge machining and at the same time higher productivity of the electroerosive process. This will make this technology more competitive compared to other advanced technologies.
Failure analysis of flexible couplings by self-heating
Authors: Grega R , Kacir M , Krajnak J
Published: November 2021

Flexible couplings are applied in mechanical systems to reduce torsional vibrations. Failures in the flexible parts of the couplings are often incorrectly attributed to overloading of the couplings. The goal of the article is to prove by experimental analysis that self-heating occurs in flexible couplings. The self-heating of the flexible coupling and the consequent increase in the temperature of the flexible part is the cause of the failure. Experimental identification of self-heating was performed on three types of flexible couplings. Although these couplings are design different, they are used for a nominal torque of 150Nm.