bluuebunny/crossref_metadata_2025 huggingface dataset:
Conflict management in healthcare institutions: the case of healthcare center Zvečan
Authors: Dobričanin Sonja , Vučinić Ivana , Tripkovic Andjelka , Radovanović Ivana
Published: February 2023

Good interpersonal cooperation is necessary for the efficient and effective work of any organization, institution, program, project or team. Conflicts are an inevitable companion of good interpersonal relations and cooperation. Effective resolution of conflicts within any organization, including healthcare organizations, should be a priority due to their direct impact on the quality of healthcare provided. The paper aims to examine the influence of interpersonal health workers on the effectiveness of the health institutions where they are employed. The paper examines whether employees in a healthcare facility are exposed to conflict situations, as well as whether there is a connection between conflicts such as negative interpersonal relationships and business efficiency, i.e., the provision of healthcare services. Furthermore, the paper examines the differences between the conflict and the sociodemographic characteristics of the respondents. The research was conducted in the Healthcare center in Zvečan (Kosovska Mitrovica) through a survey. The research sample (N=103) consisted of employees in the aforementioned health institution.
The influence of social networks on the recruitment process in tourism and catering enterprises
Authors: Sančanin Branislav , Ratković Njegovan Biljana , Brdar Ivana
Published: February 2023

The continuous striving to secure a competitive advantage in a dynamic and changing global space is increasingly shifting towards the labor market. To attract potential and retain qualified staff, tourism and hospitality organizations allocate significantly more funds and time to the task than previously. In this context, the use of social networks is viewed from two diametrically opposed platforms: ever more employers visit social networks to obtain additional information on candidates; while viewed from the perspective of potential candidates, their intention to get to know the employer, its image and reputation corresponds with their decision on whether or not they will be applying for a vacancy. The aim of the research is to determine the connection between the methods of the human resources recruitment process for managerial positions, technical/professional jobs and for interns, and the social networks where they advertise those vacancies. Five social networks were taken into account: Facebook, Twitter, LinkedIn, YouTube and Instagram. The research was conducted within the Republic of Serbia from May 1 to June 30, 2021, and the sample included 133 respondents.
COVID-19 and profitability of hotel companies in the Republic of Serbia
Authors: Knežević Snežana , Milašinović Marko , Džafić Goran , Obradović Tijana
Published: February 2023

Besides obvious negative consequences for people's health, the COVID-19 pandemic placed significant negative consequences on the economy as well. Since pandemic made tourism and travel almost impossible, these industries of tourism and hospitality suffered the most. The aim of this paper is to assess whether the onset of the COVID-19 pandemic has caused a change in the level of profitability of companies from hotel industry in the Republic of Serbia. The research sample consisted of 100 companies from hotel industry in the Republic of Serbia, where their operations in 2019 and 2020 were observed. The Operating Profit Margin, Net Profit Margin, Return on Assets and Return on Equity were used for the purposes of measuring profitability. The research determined that in the largest number of observed hotel companies in 2020, there was a decrease in profitability considering all four used indicators. By applying the Wilcoxon rank test and the t-test of paired samples, it was determined that the mentioned reductions in the used profitability indicators are statistically significant.
Effects of Marketing Indicators Application on Brand Evaluation
Authors: Janjić Ljubica , Arsić Ljiljana , Anđelković Žaklina
Published: February 2023

The brand, as a relational capital segment, represents the intangible assets of the company. Not only influencing the company performance, the value of the brand determines the future growth and development. The paper presents a comparative review of the literature, which provides a basis for creating a framework of the most valuable marketing measures for brand evaluation. Marketing metrics are selected on certain criteria, which are determined by the marketing managers. The results presented in this paper should indicate the effects on the company performance from the correct selection of marketing indicators for brand evaluation. After reviewing the theoretical achievements in the field of brand metrics, the paper presents the most important set of measures, with the greatest impact on company performance. Also, the brand balanced scorecard is explained, together with examples of balanced scorecards of certain companies. Finally, the implications of brand metrics on the company's performance are presented.
Economic indicators of profitability in the production of organic and conventional food and psychological ways of overcoming the crisis in managers due to the possible decline of business during the COVI-19 pandemic
Authors: Mitić Vladimir , Čolović Milica
Published: February 2023

The COVID-19 virus pandemic has led to huge changes in the business of many companies. Managers and owners of companies were most affected, so in one segment of this paper, certain psychological ways that are available to people when it comes to overcoming various crises. Considering that profitable business is a condition for the survival of companies, in this paper, a comparison of profitability in the production of organic and conventional food was performed. ROA and ROE were calculated on a sample of 150 food producers in our country for the period from 2016 to 2020. The results showed that ROA is higher in conventional food producers, while ROE is higher in organic food producers. During the COVID-19 pandemic, the profitability of food producers is higher than in the period before its outbreak.  Also, there is a tendency to increase profitability in both types of production.
Public oversight over audit as a determinant of its quality
Authors: Đorđević Milica , Đukić Tadija
Published: February 2023

Ensuring a high level of audit quality is a basic prerequisite for fulfilling its purpose - increasing the credibility of information contained in financial reports and functioning in the public interest. Since the self-regulation of the audit profession has not proven to be a sufficient mechanism for ensuring the quality of audits in the last two decades the need and importance of establishing and effectively functioning public oversight over audits is especially highlighted. The aim of the authors of this paper is to assess the compliance of the institutionalization of public audit oversight in the Republic of Serbia with the relevant European Union regulations and the manner of its functioning. In order to examine the direction of further development of public oversight and, in particular, its impact on audit quality, an analysis of the practice of public oversight in the Republic of Serbia for the last four years was carried out.
Korporativno dezinvestiranje kao faktor poslovnih performansi i tržišne vrednosti preduzeća
Authors: Lekpek Ahmedin , Šabotić Zenaida , Vehapi Semir
Published: February 2023

Predmet ovog istraživanja je proces dezinvestiranja i njegov uticaj na poslovne performanse i tržišnu vrednost preduzeća. Istraživanje se zasniva na pregledu relevantne strane i domaće literature koja se bavila pitanjem dezinvestiranja i njegovim uticajem na poslovni uspeh i tržišnu poziciju preduzeća. Cilj istraživanja je da se na osnovu pregleda relevenatne literature sagleda pravac uticaja procesa dezinvestiranja na poslovne performanse i tržišnu vrednost preduzeća. Rezultati pregledanih istraživanja pokazuju da dezinvestiranje ima pozitivan uticaj na poslovne performanse i tržišnu vrednost preduzeća ukoliko je inicirano od strane investitora-akcionara i sprovedeno dobrovoljno i na strateški način, na efikasnom finansijskom tržištu i u stabilnom poslovnom okruženju, od strane menadžmenta sposobnog da taj proces efikasno sprovede i uspešno upravlja preostalim poslovima.
Bending, buckling, and free vibration analysis of multi-span beams
Authors: Nikolić Aleksandar
Published: February 2023

In this paper, the modified segmented rod method (MSRM) will be used for bending, buckling, and free vibration analysis of multi-span beams. Since there is MSRM for a one-span beam in literature, slight corrections will enable the application of this method to the case of multi-span beams. The motivation for this research lies in the fact that there are engineering objects that must be modeled as multi-span beams, such as bridges. The proposed MSRM uses the absolute coordinates of the rigid segments, so the introduction of different boundary conditions as well as the loads can be done easily. The effectiveness of the MSRM was tested through numerical examples where the comparison with current results from the available literature was done.
Determination of relative weight coefficients based on thermal characteristics of materials using the F-AHP method
Authors: Bošković Goran , Čepić Zoran , Ubavin Dejan
Published: February 2023

In this paper, multi-criteria problem solving method - Fuzzy Analytical Hierarchy Process Method (F-AHP) is proposed, the goal of this paper is to implement the F-AHP procedure, which is to obtain weight coefficients based on the thermal characteristics of materials deposited in one warehouse. In subsequent research, the mentioned coefficients will be used in fire simulations inside the warehouse
Anomalies in quantum field theories
Authors: Fabiano Nicola
Published: February 2023

Introduction:purpose: Noether's theorem connects symmetry of the Lagrangian to conserved quantities. Quantum effects cancel the conserved quantities. Methods: Triangle diagram, Path integral, Pauli-Villars regularisation. Results: Quantum effects that spoil conserved quantities of local gauge symmetries endager renormalisability. Conclusion: A careful treatment of anomalies is needed in order to obtain correct results. The p 0 → gg decay is perhaps the most notable "impossible" effect allowed by anomalies.
Application of new robust design by means of probability-based multi-objective optimization to machining process parameters
Authors: Zheng Maosheng , Teng Haipeng , Wang Yi
Published: February 2023

Introduction/purpose: New robust design by means of probability-based multi-objective optimization takes the arithmetic mean value of the performance indicator and its deviation as twin independent responses of the performance indicator. The aim of this article is to check the applicability of new robust design in optimizing machining process parameters. To conduct the examination in detail, the robust design for optimal cutting parameters to minimize energy consumption during the turning of AISI 1018 steel at a constant material removal rate is applied as well as the concurrent optimization of the machining process parameters and the tolerance allocation of a spheroidal graphite cast iron piston. Methods: In the spirit of the probability-based method for multi-objective optimization, the arithmetic mean value of the performance indicator and its deviation are taken as two independent responses of the performance indicator to implement robust design. Each of the above twin responses contributes one part of the partial preferable probabilities to the performance indicator of the alternatives in the treatment. The arithmetic mean value of the performance indicator should be assessed as a representative of the performance indicator according to the function or the preference of the performance indicator, and the deviation is the other index of the performance indicator, which has the characteristic of the 99 smaller-the-better in general. Furthermore, the square root of the product of the above two parts of the partial preferable probability forms the actual preferable probability of the performance indicator. Moreover, the product of partial preferable probabilities gives the total preferable probability of each alternative, which is the overall and unique index of each alternative in the robust optimum. Results: The paper gives the rational optimum cutting parameters for minimizing energy consumption during the turning of AISI 1018 steel at a constant material removal rate and the concurrent optimization of the machining process parameters and the tolerance allocation of a spheroidal graphite cast iron piston. Conclusion: The application study indicates its rationality and convenience of new robust optimization in the optimization of machining process parameters.
Satellite remote sensing and deep learning for aerosols prediction
Authors: Mirkov Nikola , Radivojević Dušan , Lazović Ivan , Ramadani Uzahir , Nikezić Dušan
Published: February 2023

Introduction/purpose: The paper presents a new state-of-the-art method that involves NASA satellite imagery with the latest deep learning model for a spatiotemporal sequence forecasting problem. Satellite-retrieved aerosol information is very useful in many fields such as PM prediction or COVID-19 transmission. The input data set was MODAL2_E_AER_OD which presents global AOT for every 8 days from Terra/MODIS. The implemented machine learning algorithm was built with ConvLSTM2D layers in Keras. The obtained results were compared with the new CNN LSTM model. Methods: Computational methods of Machine Learning, Artificial Neural Networks, Deep Learning. Results: The results show global AOT prediction obtained using satellite digital imagery as an input. Conclusion: The results show that the ConvLSTM developed model could be used for global AOT prediction, as well as for PM and COVID-19 transmission.
Military green technology: Present and future
Authors: Miličević Zoran , Bojković Zoran
Published: February 2023

Introduction/purpose: This paper aims to present military green technology through present concepts, solutions and challenges, as well as through future trends, particularly in wireless communication. Methods: Analyses and syntheses were used to consider various aspects, challenges and developments of military green technology. Results: Important aspects of organization, challenges and strategies in military green technologies are presented. Next, the role of a green energy action plan is emphasized. Furthermore, green defence solutions and security challenges are considered. Besides presenting green technologies of today, primarily focused on wireless networks, especially 5G, the paper also considers the impact of biofuels, methanol-based fuel cells, hydrogen fuel cells, hybrid electrical vehicles and photovoltaic energy. Finally, green technologies for the future are presented through some of the most important technologies: next generation wireless networks, pulse detonation engines, piezoelectricity, and biodegradable platforms. Conclusion: Military green technology is now necessary for approaching wireless networking in order to meet challenges of high demands of wireless traffic and energy consumption. Also, military green technology will require further constant considerations in the field of efficiency and sustainability of application as well as research to provide different acceptable solutions, not only in technical, but also in the organizational domain, in order to be applied in military environment.
On the spectral radius of VDB graph matrices
Authors: Gutman Ivan
Published: February 2023

Introduction/purpose: Vertex-degree-based (VDB) graph matrices form a special class of matrices, corresponding to the currently much investigated vertex-degree-based (VDB) graph invariants. Some spectral properties of these matrices are investigated. Results: Generally valid sharp lower and upper bounds are established for the spectral radius of any VDB matrix. The equality cases are characterized. Several earlier published results are shown to be special cases of the presently reported bounds. Conclusion: The results of the paper contribute to the general spectral theory of VDB matrices, as well as to the general theory of VDB graph invariants.
An alternative theoretical model of the Earth's EM field based on two-component field hypotheses
Authors: Bjelić Slobodan , Marković Nenad
Published: February 2023

Introduction/purpose: The paper describes an alternative theoretical model of the Earth's EM field based on two-component field hypotheses. The paper consists of several parts, one part of which is a model showing the rotation of the magnetically conducting sphere of magnetization M in a foreign magnetic field. The last part defines theoretical models for the calculation of the components of the electromagnetic field of electrically conductive, dielectric and magnetically conductive spheres which are exposed to the influence of a foreign electromagnetic field. Methods: In the work, the responses of electrically conductive, dielectric and magnetically conductive spheres to the influence of external EM fields were investigated using the analytical method. Results: The obtained solutions in the form of analytical formulas will be applied to research the impact of the Sun's EM field on the planets and especially on the Earth. Conclusion: The resulting formulas of the electric and magnetic field strength and induction and their solutions can be applied to electrically conductive, dielectric and magnetically conductive spheres. In comparison to already known formulas, they are simple and have higher accuracy.
Spontaneous emission enhancement and directional emission by an optical nanonatenna array on a metallic mirror
Authors: Su Yu-Hang , Zhang Lian , Tao Can , Wang Ning , Ma Ping-Zhun , Zhong Ying , Liu Hai-Tao ,   Institute of Modern Optics, College of Electronic Information and Optical Engineering, Nankai University, Tianjin 300350, China,   Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology, Nankai University, Tianjin 300350, China,   State Key Laboratory of Precision Measurement Technology and Instruments, School of Precision Instrument and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China
Published: February 2023

Optical nanoantennas support surface plasmon polariton (SPP) with a confinement of light breaking through the diffraction limit, and thereby achieving an enhancement and regulation of electromagnetic field on a deep-subwavelength scale. In this paper, a periodic array of optical nanoantennas on a metallic mirror is proposed, where the antennas are gold nanocubes forming a two-dimensional periodic array, and a single point emission source is located in the nanogap between the antenna of gold nanocube and the gold mirror. The nanogap between the antenna and mirror can support gap surface plasmon, which results in an enhanced spontaneous emission rate. Meanwhile, the periodic array of nanoantennas can support the surface lattice resonance (SLR), which can achieve directional far-field radiation perpendicular to the substrate or in a specified direction by properly designing the array period. To design the antenna that can simultaneously achieve an enhancement of spontaneous emission rate and a directional radiation of far field, the calculation of the radiation field of a single point source in a periodic structure is transformed into the calculation of the radiation fields of a set of pseudoperiodic point-source arrays by combining the array scanning method (ASM) and full-wave rigorous numerical method, thus giving the spontaneous emission rate of the emitter and the near-field distribution of the antenna. Concerning the calculation of the angular distribution of far-field radiation intensity, we start from the Maxwell’s equations and provide a rigorous formulation and proof of the reciprocity-theorem method. This proof is different from those reported in existing literature and has a more rigorous applicability for infinite-extent periodic structures or has a lower amount of computational work. Based on the reciprocity-theorem method, the antenna parameters are designed so that the enhancement factor of far-field radiation intensity reaches a maximum value of 2756 in the direction perpendicular to the substrate, and simultaneously, the enhancement factors of total spontaneous emission rate and far-field spontaneous emission rate of the point source reach 1097 and 55.50, respectively. The proposed antenna has a simple structure that is easy to design and fabricate, and the proposed design method is intuitive and easy to implement, which can be used to guide the design of high-speed, high-brightness and directional-radiation light sources.
Coupling interactions of anisotropic hyperbolic phonon polaritons in double layered orthorhombic molybdenum trioxide
Authors: Qian Li-Ming , Sun Meng-Ran , Zheng Gai-Ge ,   School of Physics and Optoelectronic Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China,   Jiangsu International Joint Laboratory on Meterological Photonics and Optoelectronic Detection, Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment Technology, Nanjing University of Information Science and Technology, Nanjing 210044, China
Published: February 2023

The natural hyperbolic phonon polariton material-orthorhombic molybdenum trioxide (α-MoO3) has recently attracted much interest , due to the associated ultra-confinement of light and enhanced light-matter interactions. We theoretically propose and study the in-plane anisotropic phonon polaritons (APhPs) in the Kretschmann structure with monolayer and dual layers α-MoO3. The excitation of phonon polaritons and the corresponding dispersion properties in this multilayer system are studied by using a generalized 4×4 transfer matrix method (TMM). The frequency dispersions with geometrical parameters are also discussed in detail. The results confirm that the interlayer coupling can be modulated by stacking the multilayer films and regulating the thickness of each layer. More interestingly, when the distance between double α-MoO3 layers is much smaller than the propagation length of PhPs, a strong coupling phenomenon occurs, and the photon tunneling probability and intensity can be greatly improved. When the incident angle is greater than the total internal reflection angle, the phase matching condition for SPhP excitation can be satisfied. Within the 40° incident angle, the SPhP blue-shifts rapidly with the increase of incident angle. But then the dispersion curve no longer changes with increase of incidence angle. The enlargement of the interstitial layer can also lead the Fabry-Perot (FP) resonance mode to be excited. The APhP in layered heterostructure is an important part of today's nanophotonic technology, our study can help optimize and design tunable optoelectronic devices based on hyperbolic materials.
The self-assembly behavior of polymer/nanorods hybrid system under oscillation field
Authors: Wang Kang-Ying , Ma Cai-Yuan , Yu Hui-Min , Zhang Hai-Tao , Cen Jian-Yong , Wang Ying-Ying , Pan Jun-Xing , Zhang Jin-Jun ,   School of Physics and Information Engineering, Shanxi Normal University, Taiyuan 030031, China
Published: February 2023

The self-assembly behavior of diblock copolymer/homopolymer/nanorods hybrid system under oscillation field is performed by using Cell Dynamics Scheme (CDS) and Brownian Dynamics (BD). The effects of the amplitude and frequency of the oscillation field on the formation and evolution of the mixture morphology are investigated systematically. It is found that the oscillation field plays an important role in the formation and transformation of the ordered structure. With the frequency increasing, the orientation of the lamellar structure transforms from parallel to the field direction to random angle and then to perpendicular to the field direction. Compared with the pure rod system, the addition of polymers has a combing effect. Under high amplitude and low frequency (\begin{document}$ {\rm{\omega }}\leqslant 0.01 $\end{document}) of the oscillation field, the arrangement of nanorods transforms from vertical to horizontal. However, under high amplitude and high frequency (\begin{document}$ \omega > 0.01 $\end{document}), the nanorods change from vertical/horizontal hybrid arrangement to vertical arrangement. The evolution of domain size and orientation angle of nanorods under oscillation field are further analysed. The results provide a new method and reference for fabricating and regulating the ordered structure of polymer nanocomposites.
Magnetic properties and thermal stability of ultrathin TbFeCo films encapsulated by heavy metals Pt and W
Authors: Liu Jun-Hang , Zhu Zhao-Zhao , Bi Lin-zhu , Wang Peng-Ju , Cai Jian-Wang ,   School of Rare Earths, University of Science and Technology of China, Hefei 230026, China,   Ganjiang Innovation Academy, Chinese Academy of Sciences, Ganzhou 341119, China,   State Key Laboratory of Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China,   Songshan Lake Materials Laboratory, Dongguan 523808, China
Published: February 2023

Amorphous rare earth (RE)-transition metal (TM) ferrimagnetic alloy films have been intensively studied recently in spintronics and ultrafast information storage due to the large perpendicular magnetic anisotropy (PMA), ultrafast magnetization switching, and the presence of magnetization compensation and angular momentum compensation. In this work, we fabricate X/Tbx(Fe0.75Co0.25)1–x/X (0.13 ≤ x ≤ 0.32, X = SiO2, Pt and W) trilayers by magnetron sputtering, and systematically investigate the magnetic properties and thermal stabilities of the ultrathin TbFeCo films encapsulated by heavy metals Pt and W at room temperature. The 5–50-nm-thick TbFeCo films sandwiched by SiO2 exhibit PMA with magnetic compensation occurring in Tb concentration x between 0.21 with 0.24. For 3-nm- and 5- nm-thick TbFeCo ultrathin films encapsulated by Pt, however, there is no magnetic compensation observed throughout the composition range 0.13 ≤ x ≤ 0.32 with the film magnetization dominated by the FeCo moment. Nevertheless, the weakened PMA for the Pt/ultrathin TbFeCo/Pt trilayers is completely destroyed after annealing at 250 ℃. When the buffer layer and capping layer of Pt are replaced by W, the ultrathin TbFeCo films show magnetic compensation at 0.21 < x < 0.24, so do the thick TbFeCo films. The effective PMA field (HK) exceeds 11.5 T for the W/ultrathin TbFeCo/W films near the compensation composition, and remarkably, the HK decreases slowly on annealing, with PMA maintained even after annealing at 350–400℃. We further prepare [Pt/TbFeCo]5/Pt and [W/TbFeCo]5/W multilayers to clarify the origin of the huge difference between Pt/ultrathin TbFeCo/Pt and the W counterpart. It is found that there are partial recrystallization and phase separation for TbFeCo layer around the Pt/TbFeCo interface, leading to the disappearance of magnetic compensation and the deterioration of the PMA in the Pt/ultrathin TbFeCo/Pt films. With large PMA, W/ultrathin TbFeCo/W films show the presence of magnetic compensation, and excellent thermal robustness. The present study provides a promising heavy metal/RE-TM heterostructure for spintronic applications.
First-principles study of thermoelectric performance of monolayer Ge2X4S2 (X = P, As)
Authors: Yu Yue , Yang Heng-Yu , Zhou Wu-Xing , Ouyang Tao , Xie Guo-Feng ,   Hunan Provincial Key Laboratory of Advanced Materials for New Energy Storage and Conversion, School of Materials Science and Engineering, Hunan University of Science and Technology, Xiangtan 411201, China,   School of Physics and Optoelectronics, Xiangtan University, Xiangtan 411105, China
Published: February 2023

Monolayer Ge2X4S2 (X = P, As) are novel two-dimensional (2D) layered materials with suitable optical absorption properties in the visible range and high carrier mobility, so they possess broad application prospects in the photoelectric and thermoelectric fields. In this work, their thermoelectric properties are systematicly evaluated by using the first-principles and Boltzmann transport theory. For monolayer Ge2As4S2 and Ge2P4S2, their smaller phonon group velocities, low relaxation times and the large Grüneisen parameters result in ultra-low lattice thermal conductivities, which are 3.93 W·m–1·K–1 and 3.19 W·m–1·K–1 in the armchair direction, 4.38 W·m–1·K–1 and 3.79 W·m–1·K–1 in the zigzag directions at 300 K. Their electronic band structures reveal that the monolayer Ge2As4S2 is a semiconductor with a direct band gap of 1.21 eV, while the single-layer Ge2P4S2 owns an indirect band gap of 1.13 eV. Meanwhile, the twofold degeneracy of valence band provides a large p-type Seebeck coefficient that is 1800 μV·K–1 for Ge2P4S2 and 2070 μV·K–1 for Ge2As4S2 in the armchair direction. Obviously, monolayer Ge2X4S2 has smaller lattice thermal conductivity and higher power factor, thus it is worth exploring their thermoelectric properties. The results prove that monolayer Ge2As4S2 and Ge2P4S2 have outstanding thermoelectric performances at 500 K when they are treated by optimal n-type doping. The maximum ZT values of monolayer Ge2As4S2 and Ge2P4S2 are 3.06 (armchair direction) and 3.51 (zigzag direction), as well as 3.21 (armchair direction) and 2.54 (zigzag direction), indicating that monolayer Ge2X4S2 can be a potential candidate in the medium-temperature thermoelectric applications.
Study on avalanche ruggedness of high voltage IGBTs
Authors: Yang Wu-Hua , Wang Cai-Lin , Zhang Ru-Liang , Zhang Chao , Su Le ,   Department of Electronic and Engineering, Xi’an University of Technology, Xi’an 710048, China
Published: February 2023

With the increase of IGBT voltage and current ratings, the avalanche effect has become an important factor limiting the safe operating area (SOA) of the device. The hole injection of the p+n junction on the back of the device when the avalanche effect occurs is the main feature that distinguishes the avalanche effect of the IGBT from other devices. In this paper, the avalanche breakdown characteristics of IGBT and the behavior of avalanche-generated current filaments are studied through theoretical analysis and numerical simulation, and the physical mechanism dominating the behavior of avalanche-generated current filaments is revealed. The results show that the hole injection on the backside of IGBT leads to an additional negative differential resistance branch on the avalanche breakdown curve, and the strength of the negative differential resistance effect depends on the common base current gain of IGBT αpnp. With the increase of αpnp, the negative differential resistance effect becomes stronger, the avalanche current at the valley point where the additional negative differential resistance branch transforms into the positive differential resistance branch also becomes higher. And the valley point at the avalanche breakdown curve of IGBT dominates the strength of the avalanche-generated filament. As a result, the strength of avalanche-generated filament depends on the αpnp. With the lattice temperature increasing, the avalanche breakdown voltage of IGBT increases, leading to the shifting of the avalanche breakdown curve towards a higher voltage. And with the increase of αpnp, the offset of the avalanche breakdown curves at high and low temperature becomes smaller, which dominates the lateral movement speed of the avalanche-generated filament. With the increase of the αpnp and the decrease of the offset of avalanche breakdown curves at high and low temperature, the avalanche-generated filament laterally moves more slowly. To sum up, with the increase of the αpnp of IGBT, the avalanche-generated filament becomes stronger and moves more slowly, which extremely causes the local overheating where the filaments exist and lowers the avalanche robustness of the device. Therefore, the αpnp of IGBT must be controlled precisely in order to have a good trade-off between the characteristics and the reliability of IGBT.
Formation of oxygen vacancy clusters in Li-rich Mn-based cathode Materials of lithium-ion batteries: First-principles calculations
Authors: Shi Xiao-Hong , Hou Bin-Peng , Li Zhi-Shuo , Chen Jing-Jin , Shi Xiao-Wen , Zhu Zi-Zhong ,   College of Physical Science and Technology, Xiamen University, Xiamen 361005, China,   Hongzhiwei Technology (Shanghai) Co. Ltd., Shanghai 200120, China
Published: February 2023

Using the first-principles method, the formation energy values of O-vacancy clusters of two Li-rich Mn-based ternary cathode materials of lithium ion battery with different amounts of nickel , i.e. Li1.2Ni0.32Co0.04Mn0.44O2 (space group \begin{document}$R\bar{3}m)$\end{document} and Li1.167Ni0.167Co0.167Mn0.5O2 (space group C2/m), are calculated. Results show that the formation energy of oxygen vacancy cluster of the material with less nickel content Li1.167Ni0.167Co0.167Mn0.5O2 can be always higher than that of the material Li1.2Ni0.32Co0.04Mn0.44O2 with higher nickel content. This indicates that the oxygen vacancy clusters are more likely to form in cathode material with higher nickel content. The formation energy of the oxygen vacancy cluster near the transition metal is always greater than that near the lithium ion, indicating that the removal of oxygen tends to occur near the Li ion. Lower temperature and higher partial pressure can increase the formation energy of oxygen vacancy cluster, and therefore inhibit the formation of oxygen vacancy cluster. In addition, the formation energy values of oxygen vacancy clusters with the transition metals in the materials replaced by other transition metals (i.e., Ti and Mo) are also calculated. The results show that, in addition to the case of Ni replaced by Ti near the double oxygen vacancies near the Li-ion in Li1.2Ni0.32Co0.04Mn0.44O2, all the remaining cases of the transition metals Ni or Mn replaced by Ti or Mo always increase the formation energy of the O-vacancy cluster. Therefore, the doping should be able to inhibit the loss of oxygen and improve the structural stability of material.
The β relaxation process of La-based amorphous alloy: Effect of annealing and strain amplitude
Authors: Meng Shao-Yi , Hao Qi , Lyu Guo-Jian , Qiao Ji-Chao ,   School of Mechanics, Civil Engineering and Architecture, Northwestern Polytechnical University, Xi’an 710072, China
Published: February 2023

The dynamic relaxation process of amorphous alloys is an important issue to understand the diffusion behavior, plastic deformation as well as glass transition phenomenon. In the current research, (La0.6Ce0.4)65Al10Co25 amorphous alloy with a pronounced β relaxation process was selected as a model system to study the dynamic mechanical relaxation processes. Influence of driving frequency, physical aging and applied strain amplitude on the β relaxation of the La-based metallic glass was probed process using dynamic mechanical analysis. The experimental results demonstrated that the peak of the β relaxation process shifts to high temperature by increasing the driving frequency. Physical aging below the glass transition temperature induces a decrease of the intensity of the β relaxation process. The “defects” of amorphous alloy decreases during the physical aging process, which is ascribed to the glassy system shifts to more stable state induced by physical aging treatment. In parallel, the intensity of the β relaxation process of the amorphous alloy increases by increasing strain amplitude. The research sheds new light on further understanding the physical origin of β relaxation process of the amorphous alloy.
Naturens trøst og trøstens natur
Authors: Thorsen Rolf
Published: February 2023

Dette essayet er en undring om å finne trøst i naturen. Fortellinger brukes for å få frem ulike aspekter ved fenomenet trøst både i og utenfor naturen, slik vi kan møte det i sorg og annen lidelse. Hensikten er ikke å slå fast hvordan noe er, men å avdekke nye aspekter ved fenomenet. Tilnærmingen er fenomenologisk og følger en dansk livsfilosofisk tradisjon. Teksten er en ytre og indre vandring gjennom livserfaring, kunst, litteratur og poesi.
Método de Análise Hierárquica (A.H.P.) para decisão de luminosidade em ambientes residenciais
Authors: Pacheco Diego Júlio , Maciel Felipe Ramos , Pacheco Livia Júlio
Published: February 2023

Há no mercado uma significativa variedade de modelos de lâmpadas apropriadas para ambiente residencial, e suas características variam consideravelmente, uma vez que a tecnologia empregada na geração de luz não é única, permitindo a existência de lâmpadas de diferentes tipos. A escolha de um modelo de lâmpadas para cômodos de uma residência é o problema utilizado para ilustrar a aplicação do Método da Análise Hierárquica (Analytic Hierarchy Process - A.H.P.), uma técnica consagrada de análise multicritério para auxílio a decisão. No momento em que as tradicionais lâmpadas incandescentes estão sendo retiradas do mercado, é válido observar as alternativas disponíveis e comparar seu desempenho. Foram selecionados quatro modelos de lâmpadas dotadas de mecanismos distintos de funcionamento, e julgadas nos termos do método A.H.P. Verificou-se que, embora um alto investimento inicial seja exigido, o modelo da lâmpada de LED, marcada pela qualidade e pelo conceito ecológico, se sobressaiu pela durabilidade, design e eficiência e apresentou um desempenho fortemente superior as demais alternativas avaliadas.
Quality Control in Clinical Biochemistry Laboratory-A Glance
Authors: Naphade Manoj , Ankur Panchbudhe Sanjyoti , Rajendra Shivkar Rajni
Published: February 2023

Quality Control (QC) is a process, designed to ensure reliable test results. It is a part of overall quality management of the laboratory in terms of accuracy, reliability and timeliness of reported test results. Two types of quality control are exercised in clinical biochemistry: Internal quality control and external quality assurance. Internal Quality Control (IQC), are the methods, which are performed every day by the laboratory personnel with the laboratory’s materials and equipment. It checks primarily the precision (repeatability or reproducibility) of the method. External Quality Assurance Service (EQAS) which are performed periodically (i.e. every month, every two months, twice a year) by the laboratory personnel, It checks primarily the accuracy of the laboratory’s analytical methods. Consequences of inaccurate results could be unnecessary treatment, treatment complications, failure to provide the proper treatment, delay in correct diagnosis, additional and unnecessary diagnostic testing leading to result in increased cost, in time and personnel effort and often in poor patient outcomes. By running quality control, a laboratory self-monitors its testing process and substantiate that the results produced are accurate and precise. Quality management system, looking at every aspect of the laboratory from sample collection to result dispatch is very important for achieving good laboratory performance. A QC programme allows the laboratory to differentiate between normal variation and error. This review article outlines indispensable role of quality control in clinical biochemistry laboratory which ensures patient satisfaction, the credibility of laboratory, generate confidence in laboratory results and reduce unnecessary financial burden.
Ameloglyphics-An Advancement in Forensic Science
Authors: Ganeshani Harshita Ramdev , Madhu Priyanka Paul , Mantri Namrata J , Datkar Dushyant
Published: February 2023

The human teeth are considered as hard tissues similar to finger impressions (trustworthy means in a body found before decay or marring). Forensic dentistry is a comparatively young science that employs the awareness of dentists to assist the legal system. It has recognised itself as a vital science in medical and legal problems, particularly in the areas of individual recognition, sex determination, and age approximation. Teeth are highly repellent to surrounding influences like erosion, dehydration, putrefaction, and they can be utilised as criminal proofs. Skeletal remains, particularly teeth, can be used to identify people in crimes and catastrophic disasters. Enamel rod end motifs have recently become prominent as a subject of study. Ameloglyphics is a phrase that has been used to describe the investigation of these prints. The tooth imprints are one of a kind with differences between teeth from different people as well as within the same person. In terms of criminal dental recognition, mostly when it comes to recognising preys of man-made disasters, such as multiple casualties in army conflicts and wars, new and applicable methods of recognition and validation are urgently needed. This review article focuses on the rationale for employing enamel rod end patterns, as well as the methods for collecting them and identifying their sub-patterns and further suggests these tooth prints as analogues for fingerprints in deceased identification in disasters, crimes and other tragedies.
Assessment of Credit Pattern of Small and Marginal Farmers in Cauvery Delta Zone of Tamil Nadu, India
Authors: Mohanraj V. , Balasubramaniam P.
Published: February 2023

Finance is the lifeblood of any business same way credit is the lifeblood of agriculture. Without credit, farmers cannot do farming activities. Hence the Primary Agricultural Credit Co-operative Societies provide credit to farm and non-farm activities in rural areas to improve agriculture. The adequate and timely availability of credit at reasonable rates is crucial for agricultural development. The study is based on households’ survey conducted in six blocks from three districts viz., Ammapettai and Orathanadu blocks of Thanjavur district, Needamangalam and Mannargudi blocks of Thiruvarur district, Kilvelur and Thirumarugal blocks of Nagapattinam district. Two villages from each block were selected purposively based on more area under rice cultivation. Sample size of 366 farmers which consisted of 183 marginal and 183 small farmers was selected randomly based on proportionate random sampling method. The data were statistically tabulated and analyzed by calculating simple percentages and cumulative square root frequency method for categorization. Nearly one-fourth of the farmers (24.86%) had low level of credit orientation followed by 23.50 per cent had very low level, 21.58 per cent had high level, 15.03 per cent of farmers had medium and very high level of credit orientation. The small farmers having high credit orientation than marginal farmers, the most of the small farmer’s occupational status was farming and business. They utilize credit for their farm, household and non-farm activities. More than three-fifth of the marginal farmers (63.39%) sometimes relying on individual moneylenders for their credit source followed by 45.36 per cent of small farmers sometimes rely on individual money lenders for their credit source and more than half of the farmers (54.37%). Most of the marginal and small farmers were having low to medium level of income category, they depend on banks, co-operative societies and money lenders for their credit source. Mostly they allocate equal percentage of loan for the farm and household expenses. The policy makers can make note of the utilization pattern of agricultural credit and can give directions on the lending terms and conditions.
Spelling Adventure Unveiled: Charting the English Language Journey of Grade Three Students in a Bhutanese School
Authors: Wangmo Sonam , Sharma Dhanapati , Tshering Gembo
Published: February 2023

The aim of this study is to investigate the types of spelling errors made by the Grade three students in English in Gedu Higher Secondary School. The study also tells the major sources underpinning such errors in contextual writing composition tasks. The data were collected from written samples of 18 students (male and female) of grade three students of Gedu HSS. The students were given 45 minutes to write on one of five different short essay topics. The spelling errors found in the writing samples were analyzed and classified into four categories of errors based on Cook's classification: omission, substitution, insertion, and transposition. An analysis of errors showed that errors of substitution were the highest proportion of errors. The most common spelling errors of the students were the wrong use of vowels and punctuation. Furthermore, the problem of spelling errors and the causes of these spelling errors results were also discussed.
Molecular Characterization and Antibiogram of Staphylococcus and Pseudomonas Species Isolated from Patients Attending Rivers State Teaching Hospital, Nigeria
Authors: Oparaodu U. , Kpormon L. B. , Odu N. N.
Published: February 2023

Disease of ear, nose and throat (ENT) affect the functioning of adults as well as children, often with significant challenge to of the daily life of affected patients. Staphylococcus and Pseudomonas species are the most prevalent etiologic agent of ENT infections. Therefore the aim of this study was to determine the antibiogram of molecularly Characterized the Staphylococcus and Pseudomonas species in the Ear and Throat among Patients Attending Rivers State Teaching Hospital. Total number of eighty samples of throat swab, and aural (ear) swab were collected aseptically using sterile Evepon swab sticks and the sample collected were properly labelled with patients' number, date and the side. The swabs were immediately transported with a transportation medium in sterile cotton plugged test tube to the microbiology laboratory for further analysis. Qquestionnaires were administered for degraphic data collections. Each throat and aural swab sample was inoculated onto Mannitol salt agar and Cetrimide agar plates for isolation of Staphylococcus and Pseudomonas species respectively. The plates were incubated at 37°C and examined for growth after 24-48 hours. Pure culture of the isolates were primarily identified biochemically and confirmed using molecular approaches. Antibiogram of the isolates was performed by the Kirby-Bauer disk diffusion method on Mueller-Hinton agar according to Clinical and Laboratory Standards Institute guideline. Results shows that out of the 50 ear swabs and 30 throat swab samples, 17 (34%) and 8 (26.7%) of the throat swabs ear swabs were positive of Pseudomonas spp. While for the Staphylococcus spp. 8 (16%) out of the 50 ear swabs and 4 (13.7%) out of 30 throat swabs were positive. The molecular results of the isolates shows that Pseudomonas fluorescens NR_115715.1, Pseudomonas aeruginosa NR_113599.1.

Staphylococcus aureus NR_113956.1. were the predominates species isolated from both ear and throat swabs. The results of antibiogram of the Staphylococcus and Pseudomonas species isolated revealed that commonly uses antibiotics especially Ceftazidime, Cefuroxime, Cloxacillin Gentamicin and Augmentin were 100% resistant to the isolates only Ofloxacin, Ceftriaxone and Nitrofurantoin were susceptible to the isolates with a percentage of 80.2%, 85.7% and 90%. The findings of this study points to the high level of frequent and indescrimate uses of antibiotics among patient suffering from symptoms of ENT resulting to difficulty in the treatment of infections using common antibiotics. It is strongly recommended that ccontinuous monitoring of patients is required for preparing antibiograms. These susceptibility results will help the physician for deciding the empirical regime for the patients.