bluuebunny/crossref_metadata_2025 huggingface dataset:
Change Management Strategy for the Activities of Business Organizations
Authors: Avdeeva Irina , Golovina Tatyana , Polyanin Andrey
Published: January 2021

Within the context of modern management, business organizations need to realize that everything around them is changing: the rules of the game, the participants, the scale of activities, and the size of markets. In other words, nothing is constant. The changes may be both local and global, whereby developments may affect different fields: executive and administrative, technical and economic, social and public, informative and analytical. Managerial decisions taken inside an organization under the aforementioned conditions require sound theoretical grounds for selection in terms of potential risks and current and future economic effects. Traditionally, long-term decisions on setting goals for an activity of a business organization and determining ways to achieve them are considered within the framework of strategic planning, as a result of which a development strategy is formed. However, under current circumstances, the place and role of change management in the strategy of business organizations requires reinterpretation. The academic originality of this contribution lies in the specification of a concept for change management with regards to the activities of business organizations based on a strategic approach and adaptation to dynamically changing market conditions, including long-term planning. As part of the study, the essence of a strategic approach to change management regarding the activities of business organizations is considered, the principles of building a change management strategy are highlighted, and an algorithm for its development and implementation is proposed.
Comparison of Value Added within EU in Terms of Corporate Investment in Research and Development
Authors: Kostiuk Yaroslava , Korená Kristína
Published: January 2021

Globalization has accelerated the growth of innovation in many countries outside the European Union. In order to remain competitive, companies and individual EU economies therefore support the development of innovations through investments in research and development.

This contribution is focused on the specification of value added in terms of investments in research and development in the construction and manufacturing sectors. Using statistics of the European Commission for the period 2013 – 2017, a dataset of 269,892 companies in the EU28 countries was generated.

The purpose of this contribution is to determine to what extent investment in research and development participates in the creation of value added. A research question was formulated to determine the ideal ratio between value added and investment.

Methods: To achieve the objectives set, regression analysis of neural networks was applied using Statistica software.

The results of the research indicate that the optimal values in the construction sector were achieved by Great Britain (~EUR 11.3 billion.) and France (~EUR 16.1 billion), and in the manufacturing sector by France (~EUR 11.42 billion), Italy (~EUR 11.41 billion) and Great Britain (~EUR 10.6 billion).

The authors consider the method of regression analysis and neural networks to be appropriate for examining the optimal ratio between investment in R&D and value added.
Comprehensive Concept Model for Management Auditing in SMEs
Authors: Kušnirová Romana
Published: January 2021

The aim of this contribution is to present managers and owners of SMEs with a comprehensive concept for the preparation and implementation of a systemic approach to management auditing. The concept is presented in the form of a model called the “Systemic Approach to Management Audits”, as developed by the author. The principle behind the model is to conduct individual audit activities according to a predetermined order, as represented by a sub-model called “Advised Activities during Management Audits”. The model, or the application of a purposeful, standardized and, above all, systemic approach, was compiled on the basis of a two-phase questionnaire survey conducted in 2015/2016 and 2018/2019 among managers of SMEs, as well as guided interviews with professional auditors. The partial aim is to also highlight the relatively poor knowledge and implementation of management auditing in SMEs, and to encourage the use of the presented methodology by them.
Economic Growth, Investment, Population Growth and Unemployment in Ethiopia
Authors: Oshora Betgilu , Nguse Tiblets , Fekete-Farkas Maria , Zeman Zoltan
Published: January 2021

The study examines the correlation between economic growth, investment, population growth and unemployment in Ethiopia. For the purposes of this study, secondary time series data collected from the National Bank of Ethiopia, IMF and World Bank databases were used. The study extracts the perceived relationship between the variables through principal component (PCA) analysis. Both the Kaiser-Meyer-Olkin measure of sampling adequacy and Bartlett’s test of sphericity were used to determine the appropriateness of the dataset for PCA. The results revealed that an increase in unemployment is positively correlated, but in the opposite direction to economic growth, investment, total population and the working-age population. On top of the rapid spread of COVID-19, the present protests as a result of the political instability and ethnic problems across the country will lead to an increase in unemployment and the loss of many lives. Policymakers therefore need to emphasize and assure an increase in economic growth and investment in order to create more jobs in line with the increasing demand for jobs, particularly by young people. Moreover, the government must address the ongoing ethnic problems and political instability before it hits the economy adversely.
Motivational Factors Used to Stimulate the Creativity of Employees in Companies Operating in the Czech Republic
Authors: Balková Miluše , Ližbětinová Lenka
Published: January 2021

Current circumstances are forcing companies to react quickly to the changes that are taking place. Maintaining competitiveness and survival depends on adaptability and the search for innovations. The goal of modern human resource management is to stimulate employees to be creative and utilise their potential. The aim of this study is to find out what motivational factors Czech companies use to stimulate and encourage the creativity of their employees and whether the chosen factors for achieving this are related to company size.
The NF-kB and Collagen Type 1 Expression in Dental Pulp after Treated Calcium Hydroxide Combined with Propolis
Authors: Pribadi Nirawati , Budiarti Dwita , Kurniawan Hendy Jaya , Widjiastuti Ira
Published: January 2021

Objective To analyze the expression of nuclear factor kappa B (NF-kB) and collagen type 1 on dental pulp after a treated combination of calcium hydroxide and propolis.

Materials and Methods The first maxillary molars of 30 rats were mechanically perforated. Teeth were divided into three groups of 10 for two separate extraction time frames, giving a total of 60 rats. The control groups were treated with Cention, the second treatment groups were treated with calcium hydroxide, and the third treatment groups were treated with a combination of calcium hydroxide and propolis. Final restoration was done with Cention. The teeth were extracted on days 7 and 14, and the expression of NF-kB and collagen type I was analyzed using immunohistochemistry.

Results There is lowest NF-kB expression and highest collagen type 1 expression on dental pulp after treated with a combination of calcium hydroxide and propolis on days 7 and 14 (p < 0.05).

Conclusion The combination of calcium hydroxide and propolis inhibits pulp inflammation and stimulates regeneration through decreasing the NF-kB expression and increasing collagen type 1.
Inhibitor Index in the Clot Waveform Analysis-Based Mixing Test Differentiates among Hemophilia A without and with Inhibitors, and Lupus Anticoagulant
Authors: Shimonishi Naruto , Ogiwara Kenichi , Oda Yukio , Kawabe Toshiki , Emmi Mari , Shima Midori , Nogami Keiji
Published: January 2021

Background The mixing test is used to identify the pathway to follow-up testing and is also useful for the investigation of lupus anticoagulant (LA) positivity. “To completely correct” indicates clotting factor deficiency, while “to not correct” indicates the presence of a clotting factor inhibitor including LA. “Index of circulation anticoagulant” and/or “percent correction” is used to interpret the results of mixing studies, but it does not accurately differentiate factor inhibitors from LA.

Aim To precisely differentiate hemophilia A (HA), HA with inhibitor (HA-inh), and LA using the clot waveform analysis (CWA)-based mixing test.

Methods Plasma samples from HA, LA, and HA-inh including acquired HA were incubated with normal plasma in 9:1, 1:1, and 1:9 mix ratios. From activated partial thromboplastin time CWA at 0-minute (immediately) and 12-minute incubation, the ratios of CWA parameters at 12 minutes/0 minute (inhibitor index) were assessed.

Results The inhibitor index values of CWA parameters obtained using the mixing test in a 1:1 ratio demonstrated a significant difference between HA-inh and LA but could not differentiate LA from HA-inh completely. Plasmas used for the mixing tests in 9:1 and 1:9 ratios were able to fully distinguish between HA-inh (>0.5 BU/mL) and LA. These indices significantly correlated with inhibitor titer below 40 BU/mL (r > 0.90), possibly estimating FVIII inhibitor titer from the inhibitor index. Plasmas in HA and LA could be distinguished by mixing in a 1:1 ratio at 0 minute (immediately).

Conclusion The inhibitor index from CWA-based mixing tests with a 12-minute incubation could differentiate among HA, HA-inh, and LA quickly.
A Case of Sudden Diffuse Thyroid Swelling after Fine Needle Aspiration Cytology where Changes over Time Were Confirmed by Ultrasonography
Authors: Takemoto Naoki , Ozawa Taijiro , Tamai Hitomi , Asaoka Tatsuhiro , Iwasaki Shinichi
Published: January 2021

We encountered a case of diffuse thyroid swelling after fine needle aspiration (dTSaFNA) cytology, and monitored the swelling by thyroid ultrasonography. The scan findings are reported. A 57-year-old female visited our hospital complaining of swelling in her anterior neck. She had a history of metal allergy and was not taking any medications. Because a solid cystic tumor was detected in the left thyroid lobe, we decided to perform fine-needle aspiration cytology (FNAC). When the second aspiration was performed with a 22G needle inserted into the nodule in the left lobe, the patient immediately complained of pain in her neck. Within 2 minutes, her anterior neck swelled up and ultrasonography showed vascular dilatation in the left thyroid lobe. Neck cooling with steroid injection was undertaken. However, over the next 5 minutes, the vascular dilatation also spread to the right lobe. About 15 minutes later, the vessels gradually became unclear, and the neck pain and swelling persisted, and the patient was hospitalized for observation. By the following day, all the symptoms and signs had resolved and the patient was discharged. FNA is associated with the risk of neck swelling caused by hemorrhage or dTSaFNA. To make a prompt diagnosis and provide appropriate treatment for this complication, ultrasonography could be useful.
News media representation on EU immigration before Brexit: the ‘Euro-Ripper’ case
Authors: Martins Marta
Published: January 2021

A higher level of mobility of people has marked the European Union (EU), with immigrants moving from one place to another, every year, looking for a better quality of life, often fleeing from war and poverty. In the wake of enlargement of the European Union, the United Kingdom (UK) experienced high inward migration. One of the main focuses of UK media coverage was immigration from Eastern European countries. The UK referendum on Brexit on 23 June 2016, was followed by an increase in hate crimes linked to migration issues and, subsequently, a media apparatus of toxic discourse and fear of the criminal ‘Other’. This paper aims to reveal how newspaper articles and personal comments written in response to these articles, represented creative and media-driven anxieties about ‘opening’ borders in the EU. The empirical sample builds on news media coverage of the ‘Euro-Ripper’ case, published in two UK newspapers—the Daily Mail and The Independent. Based on critical surveillance studies and cultural media studies, I elaborate on the notion of moral panic, dramatised by the media, which mobilises specific compositions of ‘otherness’ by constructing suspicion and criminalising inequality by particular social and ethnic groups and nationalities. I argue that the media portrays the dramatisation of transnational narratives of risk and (in)security, which redraws territorial borders and (re)define Britain’s global identity. The analysis shows how the news media in the Brexit vote continually raised and legitimised awareness related to the migration as a vehicle that enables the ‘folk-devil’ to cross borders. This context postulates an ideology that converges on a relationship of intransigence and criminal convictions, in the context of a politics of inclusion and exclusion. I conclude by emphasising how the media intersects different social and geographical spaces in which migration takes place. Media-constructed categories of suspicion targets have been previously created and ‘suspect communities’ have already been socially accepted, thereby confirming and reshaping understandings of their identities and communities.
100 MHz large bandwidth preamplifier and record-breaking 50 kHz scanning rate quantum point contact mode probe microscopy imaging with atomic resolution
Authors: Li Quan Feng , Wang Yang , Wang Fang , Hou Yubin , Lu Qingyou
Published: January 2021

The high-bandwidth preamplifier is a vital component designed to increase the scanning speed of a high-speed scanning tunneling microscope (STM). However, the bandwidth is limited not only by the characteristic GΩ feedback resistor RF but also by the characteristic unity-gain-stable operational amplifier (UGS-OPA) in the STM preamplifier. Here, we report that paralleling a resistor with the tunneling junction (PRTJ) can break both limitations. Then, the UGS-OPA can be replaced by a higher rate, higher antinoise ability, decompensated OPA. By doing so, a bandwidth of more than 100 MHz was achieved in the STM preamplifier with decompensated OPA657, and a higher bandwidth is possible. High-clarity atomic resolution STM images were obtained under about 10 MHz bandwidth and quantum point contact microscopy mode with a record-breaking line rate of 50 k lines/s and a record-breaking frame rate of 250 frames/s. Both the PRTJ method and the decompensated OPA will pave the way for higher scanning speeds and play a key role in the design of high-performance STMs.
Volatile or non-volatile switching? Establishing design parameters for metal-contact relays using ON/OFF hysteretic behavior (RT to 300 °C)
Authors: Kumar Sushil , Arya Dhairya Singh , Singh Pushpapraj
Published: January 2021

This Letter presents a systematic evaluation of the adhesion force between sub-micrometer metal (molybdenum) surfaces in microelectromechanical (MEMS) relays for a range of temperatures (RT to 300 °C). As adhesion force controls whether an electrostatic actuated MEMS relay will detach or remain in contact once the power is turned-off, therefore, it is essential to know the amount of adhesion force present between the interacting electrodes. We present a theoretical scheme that allows direct extraction of the adhesion force from experimentally measured data (ON/OFF-voltage) that can precisely determine the adhesion force from the micro- to nanoregime. Our model identified a clear correlation between the two properties, i.e., ON/OFF-voltage and adhesion force and applicable for any arbitrary material systems. The model is validated by experimental results with varying design parameters. The results confirm that the decreasing nature of pull-OFF voltage (13.9 V to 10.8 V) with increasing temperature ensures a large hysteresis window (∼4.7 V at 300 °C) for n = 3 × 6 and W/L−1 ∼ 6.67, where n is the contact-area dimension and W/L−1 is related to movable electrode geometry. The proposed method can be adopted for the precise designing of various logic relays or memory elements suitable for a wide temperature range.
Dual-band reflection polarization converter for circularly polarized waves based on a zigzag asymmetric split ring resonator
Authors: Shi Shengyuan , Qian Kefang , Gao Wentao , Dai Jing , Li Minhua , Dong Jianfeng
Published: January 2021

Polarization converters based on metasurfaces are one of the recently developed metadevices that can change the polarization state with designated modes, utilizing the sub-wavelength unit construction. In this paper, a kind of planar zigzag asymmetric split ring resonator (Z-ASRR) metasurface with dual bands is proposed to achieve nearly perfect polarization conversion for circularly polarized waves. Compared with the original prototype asymmetric resonant ring (ASRR), both magnitude and bandwidth have been remarkably improved for achieving a higher resonance, with the introduction of zigzag metallic wires. The reflection polarization conversion ratio possesses two peak values with 0.94 and 0.99 at 5.39 GHz and 9.65 GHz, respectively. It is also demonstrated that the introduction of extra gaps, which are closely linked with the multi-node standing wave characteristic, can control the number of resonant modes or modulate the relative bandwidth. Besides, an equivalent circuit model, the degree of zigzag bending, and the oblique incidence are further analyzed in detail. The experimental results agree well with the simulations, and this chiral metadevice could be applied for on-chip integration in an optical detection/laser, a chiral biosensor, and molecular spectroscopy.
Stiffening transition in asymmetric lipid bilayers: The role of highly ordered domains and the effect of temperature and size
Authors: Hossein Amirali , Deserno Markus
Published: January 2021

Cellular membranes consist of a large variety of lipids and proteins, with a composition that generally differs between the two leaflets of the same bilayer. One consequence of this asymmetry is thought to be the emergence of differential stress, i.e., a mismatch in the lateral tension of the two leaflets. This can affect a membrane’s mechanical properties; for instance, it can increase the bending rigidity once the differential stress exceeds a critical threshold. Using coarse-grained molecular dynamics simulations based on the MARTINI model, we show that this effect arises due to the formation of more highly ordered domains in the compressed leaflet. The threshold asymmetry increases with temperature, indicating that the transition to a stiffened regime might be restricted to a limited temperature range above the gel transition. We also show that stiffening occurs more readily for larger membranes with smaller typical curvatures, suggesting that the stiffening transition is easier to observe experimentally than in the small-scale systems accessible to simulation.
A model for defect formation in materials exposed to radiation
Authors: Davis Sergio , González-Cataldo Felipe , Gutiérrez Gonzalo , Avaria Gonzalo , Bora Biswajit , Jain Jalaj , Moreno José , Pavez Cristian , Soto Leopoldo
Published: January 2021

A simple model for the stochastic evolution of defects in a material under irradiation is presented. Using the master-equation formalism, we derive an expression for the average number of defects in terms of the power flux and the exposure time. The model reproduces the qualitative behavior of self-healing due to defect recombination, reaching a steady-state concentration of defects that depends on the power flux of the incident radiation and the material temperature, while also suggesting a particular time scale on which the incident energy is most efficient for producing defects, in good agreement with experimental results. Given this model, we discuss the integral damage factor, a descriptor that combines the power flux and the square of the irradiation time. In recent years, the scientific community involved in plasma-facing materials for nuclear fusion reactors has used this parameter to measure the equivalent material damage produced in experiments of various types with different types of radiation and wide ranges of power flux and irradiation time. The integral damage factor is useful in practice but lacks formal theoretical justification. In this simple model, we find that it is directly proportional to the maximum concentration of defects.
The distribution of OH radicals in a pulsed DC He + H2O plasma jet with the presence of a dielectric material
Authors: Lin Xin , Wang Lijun , Liu Jie
Published: January 2021

The distribution and density of OH radicals in a pulsed DC He + H2O plasma jet are studied by a two-dimensional (2D) plasma jet model. This article shows the effect of adding H2O to the pure He plasma jet on the OH density distribution and the changes of the OH density under different H2O contents. The process of streamer propagation toward the dielectric surface and development of the streamer on the dielectric surface are discussed in this article. The total OH radicals are generated from two parts in a He + H2O atmospheric pressure plasma jet (APPJ). The first part is produced with the water in ambient air outside the tube, and the other part is generated with the water in the helium flow. At the time when the streamer approaches the dielectric surface, it is found that electron-impact dissociation of H2O and electron neutralization of H2O+ are the main reactions to generate OH species and three-body combination of OH and OH with He is the main reaction to consume OH species. The OH density shows a donut shape in a pure He APPJ, while the density distribution of OH radicals under the nozzle gradually becomes uniform with the increase in the H2O content added to the helium flow, but the maximum value is at the both ends of the streamer outside the tube. The electron density initially increases with the increase in the proportion of H2O added to the He plasma jet and then gradually decreases with the H2O ratio greater than 0.5%. The enhancement of Penning ionization with the increasing H2O content is the main reason for the increase in electron density, while the increasing consumption of electrons by the excitation energy loss causes the decrease in the electron density with the H2O ratio more than 0.5%. The increase in the H2O content will bring both positive and negative effects. On the one hand, the increase in the H2O content added to the He gas flow will promote the generation of OH species. On the other hand, the decrease in the electron density caused by the increasing excitation energy loss slows the rapid growth of the reaction rates of the two main reactions related to the production of OH species. Eventually, OH density reaches saturation with the H2O ratio at 1.5% under the combined effect mentioned above.
Terahertz emission at a p-polarized laser radiation action on plasma
Authors: Frolov A. A.
Published: January 2021

Terahertz (THz) pulse emission is theoretically investigated when a p-polarized laser radiation falls on semi-bounded plasma. A significant increase in the energy of terahertz radiation is predicted when a laser pulse is incident at the angle of total reflection on the plasma with a density less than the critical value. It is shown that the THz signal amplification becomes especially strong when the ultra-short laser pulse falls at a small angle on the near critical plasma under conditions of rare electron collisions.
Comment on “The Winfree model with non-infinitesimal phase-response curve: Ott–Antonsen theory” [Chaos 30, 073139 (2020)]
Authors: Pazó Diego , Gallego Rafael
Published: January 2021

In a recent paper [Chaos 30, 073139 (2020)], we analyzed an extension of the Winfree model with nonlinear interactions. The nonlinear coupling function Q was mistakenly identified with the non-infinitesimal phase-response curve (PRC). Here, we assess to what extent Q and the actual PRC differ in practice. By means of numerical simulations, we compute the PRCs corresponding to the Q functions previously considered. The results confirm a qualitative similarity between the PRC and the coupling function Q in all cases.
Drebrin regulates cytoskeleton dynamics in migrating neurons through interaction with CXCR4
Authors: Shan Yufei , Farmer Stephen Matthew , Wray Susan
Published: January 2021

Significance

Proper neuronal migration is critical for the formation of correct neural circuits during development. Chemokines are known to facilitate neuronal migration. However, the underlying mechanism is still unclear. Here, we reveal a novel mechanism whereby the chemokine receptor (CXCR4), after being activated by its ligand, SDF-1, interacts directly with the cytoskeleton compartment via drebrin, an actin-binding protein that interacts with microtubule plus-end–binding proteins. The interaction between activated CXCR4/drebrin promotes neuronal migration. The study provides insights on the relationship between extracellular cues and intracellular components.
Ataluren and aminoglycosides stimulate read-through of nonsense codons by orthogonal mechanisms
Authors: Ng Martin Y. , Li Hong , Ghelfi Mikel D. , Goldman Yale E. , Cooperman Barry S.
Published: January 2021

Significance

Nonsense mutations giving rise to premature stop codons (PSCs) cause many diseases, creating the need to develop safe and effective translational read-through–inducing drugs (TRIDs). The current best-characterized TRIDs are ataluren and aminoglycosides. Only ataluren has been approved for clinical use, albeit in a limited context. Here, we provide rate measurements of elementary steps in a single eukaryotic translation elongation cycle, allowing us to demonstrate that ataluren and the aminoglycoside G418 employ orthogonal mechanisms in stimulating PSC read-through: ataluren by inhibiting release factor-dependent termination of protein synthesis and G418 by increasing functional near-cognate transfer RNA mispairing, which permits continuation of synthesis. We conclude that development of new TRIDs combatting PSC diseases should prioritize those directed toward inhibiting termination.
Inner ear and the balance between thrombosis and bleeding
Authors: Costa Joana Raquel , Martins Hugo , Soares Teresa , Almeida e Sousa Cecília
Published: January 2021

Introduction

This paper reports a case of spontaneous intralabyrinthine haemorrhage as a cause of sudden sensorineural hearing loss, and discussed the implications that abnormal intralabyrinthine findings may have in the treatment of these cases.

Case report

A 56-year-old woman with history of anticoagulants intake, was diagnosed with profound right-sided sensorineural hearing loss. Brain/inner ear Magnetic Resonance Imaging showed right-side labyrinthine haemorrhage. Blood tests were within the appropriate range. The patient began treatment with corticosteroids, and on the fifth day of treatment, because there was no improvement, suspend anticoagulation, for being possible and safe. The patient also started hyperbaric oxygen therapy, with mild improvement in hearing function.

Discussion

In fact, there is no consensus in literature that specifies the best management of a proven intralabyrinthine haemorrhage. Further studies with representative samples are needed in order to understand whether the suspension of anticoagulants, when possible, may have real prognostic implications, as noted in the reported case. Our case represents one of the few reported in the literature that shows the possible results of the suspension of oral anticoagulation in the recovery of the audiological and vestibular consequences of intra-labyrinthine haemorrhage.
Cross-talk between the calcium channel TRPV4 and reactive oxygen species interlocks adhesive and degradative functions of invadosomes
Authors: Vellino Sanela , Oddou Christiane , Rivier Paul , Boyault Cyril , Hiriart-Bryant Edwige , Kraut Alexandra , Martin René , Coute Yohann , Knölker Hans-Joachim , Valverde Miguel A. , Albigès-Rizo Corinne , Destaing Olivier
Published: January 2021

Invadosomes support cell invasion by coupling both acto-adhesive and extracellular matrix degradative functions, which are apparently antagonistic. β1-integrin dynamics regulate this coupling, but the actual sensing mechanism and effectors involved have not yet been elucidated. Using genetic and reverse genetic approaches combined with biochemical and imaging techniques, we now show that the calcium channel TRPV4 colocalizes with β1-integrins at the invadosome periphery and regulates its activation and the coupling of acto-adhesive and degradative functions. TRPV4-mediated regulation of podosome function depends on its ability to sense reactive oxygen species (ROS) in invadosomes’ microenvironment and involves activation of the ROS/calcium-sensitive kinase Ask1 and binding of the motor MYO1C. Furthermore, disease-associated TRPV4 gain-of-function mutations that modulate ECM degradation are also implicated in the ROS response, which provides new perspectives in our understanding of the pathophysiology of TRPV4 channelopathies.
ANALYSIS AND CHARGE CONTROL OF LITHIUM ION BATTERY WITH APPLICATION FOR OFF-GRID PV SYSTEM
Authors: Dash Smruti , Sarojini L
Published: January 2021

For the implementation of the PV micro grid, initially we designed the PV module. Once the PV module is designed we then decided to use P&O technique as an MPPT technique. The output pulse of the MPPT technique is then fed to the boost converter as gate pulse. The output of PV with dc to dc converter is then fed to DC grid from where the 3-phase Inverter with LC filter which converts the DC to 3-phase AC system and then is fed to load. Also the battery system with bidirectional controller is followed by a charge controller is also connected to DC micro grid so that the battery can charge or discharge as per the application.
Allocation of flights to land at the terminals of an airport
Authors: Kumar Pradeep , Sharma Shambhu
Published: January 2021

In this paper, an algorithm for solving flight landing problem has been developed to reduce the chaos at the airport. This algorithm starts with an initial basic feasible solution and then the algorithm works on the principle of steepest descent direction search method from current solution. The algorithm is easy to comprehend. The performance of this algorithm has been checked using a numerical example with known results. The flight landing problem is an application of Quadratic Assignment Problem. Since Quadratic Assignment Problem is NP- hard, it is quite tedious to get an optimal solution even for small size instances. However, as far as optimality of the solution is concerned, this algorithm leads to very favourable results.
Students’ perceptions of an e-commerce app
Authors: Singh Upasana G , Bharath Caitlyn
Published: January 2021

Varsity Vibe is South Africa’s first student discount application. It is available to students from the age of 18 to 25. To use Varsity Vibe, a student needs to be registered subscriber by paying the subscription fee unless you have a student achiever account with Standard Bank then subscription is free. Varsity Vibe consists of coupons from various stores across South Africa, these coupons can be redeemed by students when making an online purchase from the stores that are located on the Varsity Vibe authorised master file. The study aims to determine the University of KwaZulu-Natal (UKZN) Westville Campus students perceived use of using this e-commerce based application, Varsity Vibe. The research analysed the factors related to why students use Varsity Vibe, what they use Varsity Vibe to purchase, and the impact it has on their spending. A sample of 120 respondents from the UKZN Westville campus was used to obtain data. Data was obtained by distributing questionnaires on campus. The results obtained from the questionnaires were analysed and the following was concluded. Respondents were aware of the Varsity Vibe app, through on campus marketing. Only 45% of the users who had downloaded the app, were actually registered users. Of the 45% of registered users, only 60% were active monthly users of the app. Redemption of vouchers was low, as the deals within the province in which they were based was limited. Usage of the app, compared to the website, was more frequent. The app was perceived to be ‘easy to use’ and ‘useful’ by even the Non-IT users. Majority of the participants felt that the app would become more popular in time especially if the voucher base could be expanded to include more local based offers and the store base could be more comprehensive. Respondents expressed concern over security issues, in particular, storage of personal information and bank details, especially in the case of where your phone is stolen or misplaced.
Prospects for Handling 5G Network Security: Challenges, Recommendations and Future Directions
Authors: Lal Niranjan , Tiwari Shobhit Mani , Khare Devbrat , Saxena Megha
Published: January 2021

The cellular network is the today’s requirement, and telecommunication industries are in creatin new infrastructures and technologies to give more benefits to the end users. New generation like 5G are have various benefits as compared to old generations (1G to 4G). 5G system flexible, provides lower latency, interoperable, and 10 time faster than 4G that helps all stakeholder of 5G. As the 5G network is growing and many challenges will be arising with the development in the technologies. This paper includes background of 5G network and security challenges, recommendations and some future direction that an be considered by the organization before developing and integrating 5G. We finally give some directions to overcome these issues.
Molecular Dynamics Simulation Studies of the CL-20/DNB Co-crystal Based PBX with HTPB
Authors: Xiao Yun Qin , Sun Ting , Li Shen Shen , Xiao Ji Jun
Published: January 2021

Molecular dynamics (MD) simulations were conducted for a CL-20/DNB (2, 4, 6, 8, 10, 12-hexanitro-2, 4, 6, 8, 10, 12-hexaazaisowurtzitane/1, 3-dinitrobenzene) co-crystal based PBX (Polymer-bonded explosive) with HTPB (hydroxyl-terminated polybutadiene). The binding energies, pair correlation functions and mechanical properties of the PBX were reported. From the calculated binding energy (E
bind), it was found that the order of the binding energies between the crystalline surfaces (1 0 0), (0 1 0) and (0 0 1) and HTPB is (1 0 0) > (0 0 1) > (0 1 0). And it was also shown that the interactions between the crystalline surfaces and HTPB originate mainly from vdW energies. The pair correlation function revealed that H···O hydrogen bonds exist on the interfaces between the crystalline surfaces and HTPB. From the calculated mechanical data, the co-crystal/HTPB was inferred that the PBX has a higher buffer for external stimuli and reduces the formation probability of hot spots.
Numerical simulation of jet formation underwater by focusing annular liner
Authors: Hu Z C , Wang Z J , Yi J Y , Cui H L , Jia Z J
Published: January 2021

Basing on the application background of anti-submarine torpedo using shaped charge technology, a new structure of shaped charge liner named focusing annular liner was designed. The Autodyn-2D software was used to simulate the jet formation of this liner underwater. The result shows that: Through two times of convergence, the focusing annular liner can form one jet, this jet is thicker than normal jet. And during Secondary convergence, jet velocity and collision pressure are greatly increased.
Architecture and Algorithm of Formation control of Multi-unmanned vehicles Based on Swarm intelligence
Authors: Tian Z Y , Su B , Song W L , Fu R , Lu P Y , Li J Y , Bai C Q , Xiang S , Gao T Y
Published: January 2021

The main contents of this dissertation are the application of swarm intelligence to multi-unmanned vehicle system and the realization of cooperative control of multi-unmanned vehicle system. Firstly, this thesis introduces the research background and significance of multi-unmanned vehicle system and swarm intelligence. Secondly, we introduce the research contents of cooperative control of multi-unmanned vehicle system. Then the research status of cooperative control of multi-unmanned vehicle system in the domestic and overseas are introduced. Finally, this dissertation summarizes the mainstream types of architecture and algorithm of the multi-unmanned vehicle system.
The Research on the Test Technology of Ammunition-feed System Based on the Integration of Shooting Simulation and Driving Simulation
Authors: Wang Dong Ji , Guo Jianghua
Published: January 2021

Ammunition-feed system is a key system in special vehicles equipped with shooting weapons (such as main battle tank, self-propelled artillery, etc.). The working reliability of ammunition-feed system is very important for the operation of special vehicles. However, in terms of the use of ammunition-feed system of special vehicles in active service in various countries around the world, its reliability is often not satisfactory, which is the main reason that ammunition-feed system has not been adopted in American main battle tanks up to now. Firstly, the paper points out that one of the main causes of the poor reliability of ammunition-feed system lies in the problems existing in the traditional test methods, these problems are analyzed concretely, and puts forward the solution. —The test technology is adopted based on the integration of shooting simulation and driving simulation. Then, the paper states based on the basic concept of the test of technology of shooting simulation and driving simulation and type of simulation test device, working principle, basic function and technical characteristics, and This paper puts forward the concrete implementation of the integrated test technology of shooting simulation and driving simulation in the performance test of ammunition-feed system in special vehicles, and analysis of effects is applied. Finally, the conclusion is drawn that the application of the simulation test technology will improve the overall performance of the ammunition-feed system significantly.
Modelling plastic deformation of ultra-high molecular weight polyethylene composites under blast loading
Authors: Wei Zh , Huang G Y , Xu M M , Feng Sh Sh
Published: January 2021

Ultra-high molecular weight polyethylene (UHMWPE) fiber reinforced composites are widely used in military applications to resist threats like projectiles, debris, and blast waves due to their high specific modulus, high strength and low density. In this investigation, numerical simulations were carried out to model the dynamic response of the UHMWPE crossply plates under blast loading. An elastoplastic model including strain-rate dependent hardening was implemented in user subroutine VUMAT and was used to describe the anisotropic characteristics of the UHMWPE composites. The coupled Eulerian-Lagrangian (CEL) analysis in ABAQUS was applied to model the blast waves caused by the detonation of an explosive and their interaction with the UHMWPE plate. The numerical model was validated by the corresponding experimental results in the literature. The numerical results demonstrate that the strain rate effects made the deflection of the plate smaller and smoother, indicating that it is necessary to use a strain-rate dependent hardening.
The development status and trends of ground unmanned combat platforms
Authors: Wang H B , Li Y , Ren K , Yang L J , Han Zh H
Published: January 2021

Faced with the increasingly complex international situation and brutal military wars, the lives and safety of combat soldiers are greatly threatened. At this time, the unmanned combat platform is becoming increasingly important and has gradually become an important attack and defense force on the information battlefield. This article introduces the characteristics of the unmanned combat platform and its status quo of development at home and abroad, and combines the needs of future military wars to analyze the influence of ground unmanned combat platforms on combat capabilities and war patterns.
Bridge structural damage identification based on parallel CNN-GRU
Authors: Zou J Z , Yang J X , Wang G P , Tang Y L , Yu C S
Published: January 2021

Structural damage identification has been the focus of engineering fields, while the existing damage identification methods heavily depend on extracted “hand-crafted” features. Recently, due to the powerful feature learning capability of deep learning, it has been widely used in structural damage identification. However, those methods only consider the local dependence or temporal relation of data. Thus, in this paper, a structural damage identification method by combining the convolutional neural network (CNN) and gated recurrent unit (GRU) is proposed. The CNN model is used to extract the local dependence of data, and the GRU model is used to extract the temporal feature of data. These two extracted feature matrices are spliced horizontally to a fused eigenvector. The eigenvector is input to the final softmax classifier layer to identify the structural damage state. Experiments on a scale model of the three-span continuous rigid frame bridge shown that the CNN-GRU model performs significantly better than CNN, LSTM, and GRU models for structural damage identification.
Ocean Chlorophyll-a retrieval using GF1-WFV data-a case study of the central Bohai Sea
Authors: Zhai Z K , Lu S L , Wang P , Wang C , Tang H L , Liu D Y , Han Q Y , Guo J , Liu X H , Wei T L
Published: January 2021

Chlorophyll-a (Chl-a) concentration is an important indicator of phytoplankton bloom and water eutrophication. It is also a basic parameter of water quality. Remote sensing technology has been widely used for water quality monitoring in the past. In this study, the Chinese GF1 (Gaofen-1) WFV (Wide Field of View) images acquired on May 19th, 2016 were used to retrieve Chl-a concentration of central Bohai sea in order to assess the recovery condition of marine ecosystem which has been seriously polluted by the Penglai 19-3 platform oil spill accident in 2011. The remote sensing model of Chl-a concentration was developed using the linear regression method. The leave-one-out cross-validation (LOOCV) method showed that the average relative error and root mean square error (RMSE) between retrieved Chl-a concentration and in situ measurement was 11.67% and 0.1808, respectively. It indicated that the remote sensing model could correctly reflect the Chl-a concentration and its spatial distribution of the study area. The average Chl-a concentration in the buffer regions with the distance of 2km, 4km, 6km to the Penglai 19-3 platform was 0.32μg/L, 0.37μg/L and 0.40μg/L, respectively. They were in normal range and lower than that of the coastal waters. The spatial distribution of the result was similar to previous studies of Bohai sea in spring. These results indicated that Chl-a concentration of central Bohai sea was returned to normal after oil spill accident occurred for 5 years. The growth of phytoplankton in surface seawater has been returned to normal. The major causes for Chl-a concentration in the Bohai Sea was the land-sourced pollutant during the study period.
Integrated remote sensing and GIS approaches for land degradation neutrality (LDN) assessment in the agricultural area
Authors: Moonrut N , Takrattanasaran N , Khamkajorn T , Chaikaew P
Published: January 2021

Healthy soils sustain humans. Yet these essential land resources are often overlooked and threatened by human activities. Such changes lead to an unbalanced state of soil functions. The land degradation neutrality (LDN) concept has been developed to serve the sustainable development goals (SDGs), in particular goal No.15. Our goal was to move an idea from LDN concept to reality. We assessed the LDN status of the agricultural area in Saraburi Province, Thailand by using three indicators: (i) land use/land cover (LULC) change, (ii) land productivity (LP) change, and (iii) soil organic carbon (SOC) change. The indicator datasets recorded in 2017 and 2020 were used to investigate the land resource changes. LULC and NDVI metrics were obtained using Landsat 8 satellite images and areas were classified into agricultural and non-agricultural uses. For the SOC stocks, 78 agricultural soil samples were collected from the top 30cm by the Land Development Regional Office 1 (Pathum Thani) in 2017 and by the research team in 2020. The standard procedure used for the SOC laboratory analysis was the Walkley-Black method. The LDN status was estimated by integration of results of the three indicators based on a “one out, all out” system. Over three years, the study metrics indicated that net loss occurred in LULC covering the area of 46.99 km2 and SOC stocks declined at an average of 0.02%. However, the NDVI obtained from the estimate did not show a difference in the three-year period. This research highlighted alarming signs of soil degradation in the agricultural economics zone. Negative changes occurred in two of the three indicators which showed a tendency towards the degradation of soil capital in the long run. Counterbalancing measures to achieve equivalent losses and gains should be implemented as quickly as possible.
Establishment of Hydraulic Turbine Test Bench on the Tibet Plateau
Authors: Li H M , He Q L , Xiao Y X , Luo H Y , Zhang H , Xu X Q , Wang Z W
Published: January 2021

There are abundant water resources in Tibet plateau area. With the increasing demand for electric power, it is necessary to build hydropower stations and test bench in Tibet Plateau area. The low air pressure has an influence on the flow in the hydraulic turbine. Therefore, a hydraulic turbine test bench is designed and built in the Tibet Plateau for low pressure hydraulic turbine experiment. The laboratory building is a three-storey structure with one distribution room and two control rooms. The civil structure is designed according to the layout of two test bench. The built underground storage tank has an area of 300 m2, a 15-meter high water tower and a capacity of 50 m3, which can meet the requirements of simultaneous operation of the two test bench The maximum head of the main pump is 30 meters, the rated power of the main motor is 160 kW, and the rated power of the dynamometer is 110 kW, which can be operated in both positive and negative directions. Meanwhile, a set of measurement and control system software is designed to acquire experimental data. The test bench will meet the needs of experimental teaching and scientific research of hydraulic turbines in Plateau area, and meet the performance comparison and acceptance test of medium and small hydro-machinery.
The effect of PCM with different thermos-physical parameters on indoor temperature of Xi’an Solar Greenhouse
Authors: Du Xiaoyun , Li Pan , Zhao Caiyun , Sang Guochen
Published: January 2021

In this paper, the enthalpy method is used to simulate the influence of phase change materials (PCM) with different thermos-physical parameters on the indoor thermal temperature of solar greenhouses in Xi’an, China. The simulation results show that the temperature adjustment effect of PCM on solar greenhouses is significantly greater than common heat storage materials such as rammed soil, gravel and water. The lowest indoor temperature in the solar greenhouse increases first and then decreases with the increase of the phase transition temperature. The influence of PCM with different latent heat values on the average indoor temperature of the solar greenhouse increases first and then stabilizes. Increasing the thermal conductivity of PCM can reduce the temperature range of the solar greenhouse, but the increase in thermal conductivity has little effect on the indoor temperature when the thermal conductivity is greater than 0.4 W/(m⋅°C). For the Xi'an area, the best thermos-physical parameters of PCM used in solar greenhouses are: phase change temperature of 11 °C, latent heat value of 140kJ/kg, thermal conductivity greater than 0.4 W/(m⋅°C). This article provides a reference for the practical application of PCM in solar greenhouses.