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2022 ◽  
Vol 12 (2) ◽  
pp. 890
Author(s):  
Paweł Dra̧g

An optimization task with nonlinear differential-algebraic equations (DAEs) was approached. In special cases in heat and mass transfer engineering, a classical direct shooting approach cannot provide a solution of the DAE system, even in a relatively small range. Moreover, available computational procedures for numerical optimization, as well as differential- algebraic systems solvers are characterized by their limitations, such as the problem scale, for which the algorithms can work efficiently, and requirements for appropriate initial conditions. Therefore, an αDAE model optimization algorithm based on an α-model parametrization approach was designed and implemented. The main steps of the proposed methodology are: (1) task discretization by a multiple-shooting approach, (2) the design of an α-parametrized system of the differential-algebraic model, and (3) the numerical optimization of the α-parametrized system. The computations can be performed by a chosen iterative optimization algorithm, which can cooperate with an outer numerical procedure for solving DAE systems. The implemented algorithm was applied to solve a counter-flow exchanger design task, which was modeled by the highly nonlinear differential-algebraic equations. Finally, the new approach enabled the numerical simulations for the higher values of parameters denoting the rate of changes in the state variables of the system. The new approach can carry out accurate simulation tests for systems operating in a wide range of configurations and created from new materials.


Author(s):  
Si-Yu Xiong ◽  
Liang Tang ◽  
Qun Zhang ◽  
Dan Xue ◽  
Ming-Qiang Bai ◽  
...  

In this paper, we give a further discussion of short-distance teleportation. We propose bidirectional, rotation and cyclic rotation teleportation schemes for short-distance participants, respectively. In our bidirectional transmission scheme, the quantum channel is still an EPR pair and an auxiliary qubit in the ground state [Formula: see text], and two participants can transmit an unknown single-qubit state to each other. In the rotation and cyclic rotation schemes, bidirectional transmission is performed between two adjacent participants in turn. The unknown state qubits of the participants collapse into the ground state after one bidirectional transmission, and can be used as auxiliary qubits in subsequent bidirectional transmission. After a complete state rotation, each participant has held the unknown state of the other participants, and the last one owned by the participant is still the original unknown state. Although the schemes we proposed are applicable to a small range of transmission, they have certain advantages in saving quantum resources.


Author(s):  
A. R. Safin ◽  
I. V. Ivshin ◽  
A. N. Tsvetkov ◽  
T. I. Petrov ◽  
V. R. Basenko ◽  
...  

THE PURPOSE. Charging infrastructure is one of the factors influencing the transition to electric vehicles, as the electric vehicles in operation are characterized by a small range and a long battery charge period. Today, the development of the charging infrastructure depends only on the networks of stationary charging stations, which also have disadvantages (high cost, lack of mobility, etc.). Therefore, the purpose of this work is to study the design features of mobile electric vehicle charge units (MCSEU) for the development of draft design documentation for the creation of a new MCSEU project. This issue includes the study of the world market of manufacturers of modern mobile chargers, the study of technical and operational features that are today presented to modern energy storage and storage systems.MATERIALS. The authors of the article processed and analyzed data on the current state of the charging infrastructure in Russia and the world, based on materials from Russian and foreign authors, as well as information on the development strategy of the electric transport industry in Russia and the world, in particular, data from Madison Gas and Electric.RESULTS. The obtained analytical results are one of the aspects that will be taken into account when developing mobile charging devices for electric vehicles. This mobile charger technology significantly expands the possibilities of using electric vehicles, in particular electric vehicles, and also solves various problems of the fuel and energy complex associated with autonomous power sources and distributed generation systems.CONCLUSION. The charging infrastructure is one of the factors influencing the transition to electric vehicles, as the electric vehicles in operation are characterized by a small range and a long period of charging the traction battery. However, this process will be long and in the near future networks of charging stations will be created, including mobile charging units for electric vehicles.


2022 ◽  
Vol 14 (2) ◽  
pp. 634
Author(s):  
Chen Xu ◽  
Xianliang Zhang ◽  
Rocío Hernandez-Clemente ◽  
Wei Lu ◽  
Rubén D. Manzanedo

Forest types are generally identified using vegetation or land-use types. However, vegetation classifications less frequently consider the actual forest attributes within each type. To address this in an objective way across different regions and to link forest attributes with their climate, we aimed to improve the distribution of forest types to be more realistic and useful for biodiversity preservation, forest management, and ecological and forestry research. The forest types were classified using an unsupervised cluster analysis method by combining climate variables with normalized difference vegetation index (NDVI) data. Unforested regions were masked out to constrict our study to forest type distributions, using a 20% tree cover threshold. Descriptive names were given to the defined forest types based on annual temperature, precipitation, and NDVI values. Forest types had distinct climate and vegetation characteristics. Regions with similar NDVI values, but with different climate characteristics, which would be merged in previous classifications, could be clearly distinguished. However, small-range forest types, such as montane forests, were challenging to differentiate. At macroscale, the resulting forest types are largely consistent with land-cover types or vegetation types defined in previous studies. However, considering both potential and current vegetation data allowed us to create a more realistic type distribution that differentiates actual vegetation types and thus can be more informative for forest managers, conservationists, and forest ecologists. The newly generated forest type distribution is freely available to download and use for non-commercial purposes as a GeoTIFF file via doi: 10.13140/RG.2.2.19197.90082).


2022 ◽  
Vol 12 ◽  
Author(s):  
Stefano Mastandrea ◽  
John M. Kennedy

Usain Bolt’s Lightning Bolt pose, one arm highly extended to one side, suggests action. Likewise, static pictures of animals, legs extended, show animation. We tested a new cue for motion perception—extension—and in particular extension of dancer’s legs. An experiment with pictures of a dancer finds larger angles between the legs suggest greater movement, especially with in-air poses and in lateral views. Leg positions graded from simply standing to very difficult front and side splits. Liking ratings (a small range) were more related to Difficulty ratings (a large range) than Movement ratings (a moderate range).


Universe ◽  
2021 ◽  
Vol 8 (1) ◽  
pp. 8
Author(s):  
Mauro D’Onofrio ◽  
Cesare Chiosi

We have analyzed the distribution of early-type galaxies (ETGs) in the effective surface intensity vs. effective radius (Ie−Re) plane and in the total luminosity vs. central stellar velocity dispersion (L−σ) diagram, with the aim of studying the physical variables that allow the transformation of one space-parameter into the other. We find that the classical Faber–Jackson relation L=L0σα, in which the parameters L0 and α are confined in a small range of possible values, is incompatible with the distribution observed in the Ie−Re plane. The two distributions become mutually consistent only if luminosity is not considered a pure proxy of mass but a variable tightly dependent on the past history of mass assembling and star formation and on the present evolutionary state of the stellar content of a galaxy. The solution comes by considering the L=L0′σβ law proposed by D’Onofrio et al. in 2020, in which both L0′ and β can vary considerably from galaxy to galaxy. We will also show that the data of the Illustris numerical simulation prove the physical foundation of the L=L0′σβ law and confirm the prediction of the Zone of Exclusion (ZoE) originating from the intersection of the virial law with the L=L0′σβ relation. The ZoE is the region in the Ie−Re and Re−Ms diagrams avoided by real galaxies, and the border of which marks the condition of ‘full’ virial equilibrium with no recent significant merger events and no undergoing star formation.


2021 ◽  
pp. 119-120
Author(s):  
Martin Wight

In this note Wight critically analyses Morton Kaplan’s System and Process in International Politics. While ‘positivist theorists’ aspiring to scientific rigour have belittled philosophical works on topics such as the just war or natural law as ‘tautologous or platitudinous’, these theorists have themselves constructed ‘new edifices of tautology and platitude’. Kaplan, for example, restates ‘simple and obvious truths, in the impressive special language of his theory’. Wight lists other shortcomings. Kaplan’s ‘historical limitedness’ reflects his ‘small range of historical reference’. Kaplan’s reliance on the abstractions of game theory leads to ‘the unintentional effect’ of ‘trivialization’ of ‘the awful issues of peace and war’. Furthermore, Kaplan’s ‘analytical jargon atomises and disintegrates reality’, and this results in ‘dehumanization’ and ‘hypostatization’ of the abstractions. Finally, ‘Objectivity becomes moral neutrality’, with ‘moral content … drained off, and then added again to the stew in pinches of recognition as “parameters” or “values”’.


Author(s):  
Agnieszka M. Slowicka ◽  
Nan Xue ◽  
Pawel Sznajder ◽  
Janine K Nunes ◽  
Howard A Stone ◽  
...  

Abstract Three-dimensional dynamics of flexible fibers in shear flow are studied numerically, with a qualitative comparison to experiments. Initially, the fibers are straight, with different orientations with respect to the flow. By changing the rotation speed of a shear rheometer, we change the ratio A of bending to shear forces. We observe fibers in the flow-vorticity plane, which gives insight into the motion out of the shear plane. The numerical simulations of moderately flexible fibers show that they rotate along effective Jeffery orbits, and therefore the fiber orientation rapidly becomes very close to the flow-vorticity plane, on average close to the flow direction, and the fiber remains in an almost straight configuration for a long time. This ``ordering'' of fibers is temporary since they alternately bend and straighten out while tumbling. We observe numerically and experimentally that if the fibers are initially in the compressional region of the shear flow, they can undergo a compressional buckling, with a pronounced deformation of shape along their whole length during a short time, which is in contrast to the typical local bending that originates over a long time from the fiber ends. We identify differences between local and compressional bending and discuss their competition, which depends on the initial orientation of the fiber and the bending stiffness ratio A. There are two main finding. First, the compressional buckling is limited to a certain small range of the initial orientations, excluding those from the flow-vorticity plane. Second, since fibers straighten out in the flow-vorticity plane while tumbling, the compressional buckling is transient - it does not appear for times longer than 1/4 of the Jeffery period. For larger times, bending of fibers is always driven by their ends.


Author(s):  
Anup Kumar Biswas

By manipulating an electron that tunnels the tunnel junction of a single electron transistor, one will be able to reach a standard output logic “1” or logic “0”. The operation of the Single Electron Transistor (SET) is depending upon the bias voltage as well as the input signal(s). By varying the input voltage levels of a SET, the output voltage levels can significantly be changed on the basis of tunneling of an electron whether tunneling happened or not. As our concentration is the measuring of an unknown voltage, we are to implement a voltmeter system to provide a digital output of 3 bits whenever an unknown input voltage is kept in touching in the input terminal. A reference/standard voltage (say 8mV) will be connected in series with eight resistances ( 8 Rs) for the purpose of making a seven threshold voltages, for 7 comparators, in an ascending order of values from ground to reference voltage for seven comparators which are used in this present work. The voltmeter implemented consists of (i) a voltage divider, (ii) a set of seven comparators, (iii) seven Exclusive-OR gates and (iv) three 4-input OR gates. The concepts of implementing “Parallel Comparator based voltmeter” is discussed in two ways (i) by classical block diagram and (ii) using Single electron transistor based circuit. The measuring of an input analog voltage will not be the same as the digital output value. A 3-bit output indicates that the input analog voltage must lie on within a particular small range of voltage. The encoder circuit which is connected to the outputs of the comparators is hard to construct whenever the three terminals output are expressed with the output variables (Wi) of the comparators. For simple and user-friendly circuit, the outputs (Wi) of the comparators are modified to Di variables so as to get the same 3-bit encoder/voltmeter output. For this purpose, 7 extra component called 2-input XORs based on SET are used. Seven such XORs are set, and the output of them are passed to three 4-input OR gates according to the required logic expressions. It is found that all the output data of the voltmeter are coherently matched with the theoretical aspects. Processing delays are found out for all circuits. Power consumptions of all of them are shown in tabular and graphical forms. All the circuit we are intending to make are provided in due places with their logic circuit or simulation set and the simulation results are provided as well. Different truth tables are given for keeping track of whether input-output relationships matches with the theoretical results. We have thought of whether the present work circuits are faster or slower than the circuits of CMOS based-circuits. The power consumed at the time of tunneling event for a circuit is measured and sensed that it exists in the range between 1×10^(-18) Joules to 22×10^(-18)Joules which is very small amount. All the combinational circuits presented in this work are of SET-based.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Huiping Hu ◽  
Xinqun Huang ◽  
Majed Ahmad Suhaim ◽  
Hui Zhang

Abstract To reduce the probability of violent crimes, the deep learning (DL) technology and linear spatial autoregressive models (ARMs) are utilised to estimate the model parameters through different penalty functions. In addition, under a determinate space, the influences of environmental factors on violent crimes are discussed. By taking campus violence cases as examples, the major influencing factors of violent crimes are found through data analysis. The results show that campus violence cases are usually caused by the complex surrounding environments and persons. Also, campus security measures only cover a small range, and the security management is difficult. In the meantime, due to the younger ages and lack of self-protection awareness, students may easily become the targets of criminals. Therefore, the results have a positive significance for authorities to analyse the crime rates in a determinate area and take preventive measures against violent crimes.


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