Статті в журналах: "Modules of constant Jordan type"

1

Kaptanoğlu, Semra Öztürk. "Restricted Modules and Conjectures for Modules of Constant Jordan Type." Algebras and Representation Theory 17, no. 5 (October 19, 2013): 1437–55. http://dx.doi.org/10.1007/s10468-013-9455-6.

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2

Benson, David J. "Modules of Constant Jordan Type with One Non-Projective Block." Algebras and Representation Theory 13, no. 3 (February 6, 2009): 315–18. http://dx.doi.org/10.1007/s10468-008-9124-3.

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3

Benson, David John. "Modules of Constant Jordan Type with Small Non-Projective Part." Algebras and Representation Theory 16, no. 1 (June 11, 2011): 29–33. http://dx.doi.org/10.1007/s10468-011-9291-5.

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4

Baland, Shawn. "Modules of constant Jordan type with two non-projective blocks." Journal of Algebra 346, no. 1 (November 2011): 343–50. http://dx.doi.org/10.1016/j.jalgebra.2011.08.023.

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5

Benson, David J. "Modules of constant Jordan type and a conjecture of Rickard." Journal of Algebra 398 (January 2014): 343–49. http://dx.doi.org/10.1016/j.jalgebra.2012.10.010.

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6

Baland, Shawn. "On the generic kernel filtration for modules of constant Jordan type." Archiv der Mathematik 99, no. 4 (October 2012): 305–14. http://dx.doi.org/10.1007/s00013-012-0439-2.

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7

Benson, Dave, and Julia Pevtsova. "A realization theorem for modules of constant Jordan type and vector bundles." Transactions of the American Mathematical Society 364, no. 12 (December 1, 2012): 6459–78. http://dx.doi.org/10.1090/s0002-9947-2012-05482-1.

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8

Baland, Shawn, and Kenneth Chan. "Modules of constant Jordan type, pullbacks of bundles and generic kernel filtrations." Journal of Algebra 462 (September 2016): 253–84. http://dx.doi.org/10.1016/j.jalgebra.2016.06.002.

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9

Kaptanoğlu, Semra Öztürk. "p-Power Points and Modules of Constantp-Power Jordan Type." Communications in Algebra 39, no. 10 (October 2011): 3781–800. http://dx.doi.org/10.1080/00927872.2010.512585.

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10

Zhelyabin, V. N. "Jordan superalgebras of vector type and projective modules." Siberian Mathematical Journal 53, no. 3 (May 2012): 450–60. http://dx.doi.org/10.1134/s0037446612020267.

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11

SHEN, Y., G. S. ZHOU, and D. M. LU. "REGULARITY CRITERION AND CLASSIFICATION FOR ALGEBRAS OF JORDAN TYPE." Glasgow Mathematical Journal 58, no. 1 (July 21, 2015): 69–95. http://dx.doi.org/10.1017/s0017089515000075.

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AbstractWe show that Artin–Schelter regularity of a $\mathbb{Z}$-graded algebra can be examined by its associated $\mathbb{Z}$r-graded algebra. We prove that there is exactly one class of four-dimensional Artin–Schelter regular algebras with two generators of degree one in the Jordan type. This class is strongly noetherian, Auslander regular, and Cohen–Macaulay. Their automorphisms and point modules are described.

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12

Liu, Qi, Anwarud Din, and Yongjin Li. "Some aspects of generalized von Neumann-Jordan type constant." AIMS Mathematics 6, no. 6 (2021): 6309–21. http://dx.doi.org/10.3934/math.2021370.

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13

Yang, Changsen, and Xiangz ao Yang. "On the James type constant and von Neumann-Jordan constant for a class of Banaś-Fraczieck type spaces." Journal of Mathematical Inequalities, no. 2 (2016): 551–58. http://dx.doi.org/10.7153/jmi-10-43.

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14

Ghanem, Fatima. "Geotechnical Engineering Evaluation of Superficial Deposits Utilizing Seismic Methods at Al al-Bayt University, Jordan." Iraqi Geological Journal 54, no. 1D (April 30, 2021): 11–28. http://dx.doi.org/10.46717/igj.54.1d.2ms-2021-04-22.

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Integration of seismic refraction tomography and multi-channel analyses shear wave methods were used at Al al-Bayt university campus in Mafraq, NE Jordan to delineate the shallow subsurface layering and determine their geotechnical properties, in addition, to estimate the geotechnical engineering parameters of the superficial deposits for detailed purposes. The P-wave refraction velocities were found to range from 180 to 2300 m/s for the three identified layers which indicating superficial soil deposits with an increasing degree of compaction with depth. The S-wave velocities were found to lie in a narrow velocity range (250 to 600 m/s), which badly resolved the subsurface layering. Moreover, four soil samples were taken from the sites of seismic survey points for density calculations. The average calculated density was found to be 1.85 g/cm3. Two soil samples from nearby seismic profile-1 and seismic profile-4 were tested for geotechnical properties. The results showed that the seismic method is an effective tool to estimate the different elastic moduli; Poisson's ratio, Young's modulus, Bulk modulus, Shear modulus, Lame's constants, and geotechnical engineering parameters; N-value, bearing capacity, material index, concentration index, and stress ratio of the superficial soil deposits. The study recommends conducting a detailed geophysical study before starting any type of geoengineering construction in the area.

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15

Zuo, Zhanfei, Chun-Lei Tang, Xiaoc un Chen, and Liang ei Wang. "Jordan-von Neumann type constant and fixed points for multivalued nonexpansive mappings." Journal of Mathematical Inequalities, no. 3 (2016): 649–57. http://dx.doi.org/10.7153/jmi-10-52.

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16

Bissinger, Daniel. "Representations of constant socle rank for the Kronecker algebra." Forum Mathematicum 32, no. 1 (January 1, 2020): 23–43. http://dx.doi.org/10.1515/forum-2018-0143.

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AbstractInspired by recent work of Carlson, Friedlander and Pevtsova concerning modules for p-elementary abelian groups {E_{r}} of rank r over a field of characteristic {p>0}, we introduce the notions of modules with constant d-radical rank and modules with constant d-socle rank for the generalized Kronecker algebra {\mathcal{K}_{r}=k\Gamma_{r}} with {r\geq 2} arrows and {1\leq d\leq r-1}. We study subcategories given by modules with the equal d-radical property and the equal d-socle property. Utilizing the simplification method due to Ringel, we prove that these subcategories in {\operatorname{mod}\mathcal{K}_{r}} are of wild type. Then we use a natural functor {\operatorname{\mathfrak{F}}\colon{\operatorname{mod}\mathcal{K}_{r}}\to% \operatorname{mod}kE_{r}} to transfer our results to {\operatorname{mod}kE_{r}}.

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17

Stewart, David I. "On the minimal modules for exceptional Lie algebras: Jordan blocks and stabilizers." LMS Journal of Computation and Mathematics 19, no. 1 (2016): 235–58. http://dx.doi.org/10.1112/s1461157016000103.

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Let $G$ be a simple simply connected exceptional algebraic group of type $G_{2}$, $F_{4}$, $E_{6}$ or $E_{7}$ over an algebraically closed field $k$ of characteristic $p>0$ with $\mathfrak{g}=\text{Lie}(G)$. For each nilpotent orbit $G\cdot e$ of $\mathfrak{g}$, we list the Jordan blocks of the action of $e$ on the minimal induced module $V_{\text{min}}$ of $\mathfrak{g}$. We also establish when the centralizers $G_{v}$ of vectors $v\in V_{\text{min}}$ and stabilizers $\text{Stab}_{G}\langle v\rangle$ of $1$-spaces $\langle v\rangle \subset V_{\text{min}}$ are smooth; that is, when $\dim G_{v}=\dim \mathfrak{g}_{v}$ or $\dim \text{Stab}_{G}\langle v\rangle =\dim \text{Stab}_{\mathfrak{g}}\langle v\rangle$.

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18

Ciesielski, Maciej, and Ryszard Płuciennik. "On some modifications of n-th von Neumann–Jordan constant for Banach spaces." Banach Journal of Mathematical Analysis 14, no. 3 (January 1, 2020): 650–73. http://dx.doi.org/10.1007/s43037-019-00033-1.

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AbstractWe study, among others, upper, lower, upper modified and lower modified n-th von Neumann–Jordan constant and relationships between them. There are characterized uniformly non-$$l_{n}^{1}$$ l n 1 Banach spaces in terms of the upper modified n-th von Neumann–Jordan constant. Moreover, this constant is calculated explicitly for Lebesgue spaces $$L^{p}$$ L p and $$l^{p}$$ l p $$(1\le p\le \infty ).$$ ( 1 ≤ p ≤ ∞ ) . Finally, it is shown that the sequence of n-th upper and modified upper von Neumann–Jordan constants for the space $$L^p$$ L p as well as $$l^p$$ l p $$(2<p<\infty )$$ ( 2 < p < ∞ ) converges to $$B_p^2$$ B p 2 , where $$B_p$$ B p is the best type (2, p) constant in the Khinthine inequality for the case $$2\le p<\infty $$ 2 ≤ p < ∞ .

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19

Zuo, Zhanfei, Liang ei Wang, Yong-Xiang Zhao, and Yan-Qiu Wu. "On the generalized von Neumann-Jordan type constant for some concrete Banach spaces." Mathematical Inequalities & Applications, no. 3 (2021): 597–615. http://dx.doi.org/10.7153/mia-2021-24-42.

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20

Zuo, Zhan-fei. "The generalized von Neumann-Jordan type constant and fixed points for multivalued nonexpansive mappings." ScienceAsia 45, no. 3 (2019): 292. http://dx.doi.org/10.2306/scienceasia1513-1874.2019.45.292.

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21

REIF, JOHN, and SAM SLEE. "ASYMPTOTICALLY OPTIMAL KINODYNAMIC MOTION PLANNING FOR A CLASS OF MODULAR SELF-RECONFIGURABLE ROBOTS." International Journal of Computational Geometry & Applications 21, no. 02 (April 2011): 131–55. http://dx.doi.org/10.1142/s0218195911003585.

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Self-reconfigurable robots are composed of many individual modules that can autonomously move to transform the shape and structure of the robot. The task of self-reconfiguration, transforming a set of modules from one arrangement to another specified arrangement, is a key problem for these robots and has been heavily studied. However, consideration of this problem has typically been limited to kinematics and so in this work we introduce analysis of dynamics for the problem. We characterize optimal reconfiguration movements in terms of basic laws of physics relating force, mass, acceleration, distance traveled, and movement time. A key property resulting from this is that through the simultaneous application of constant-bounded forces by a system of modules, certain modules in the system can achieve velocities exceeding any constant bounds. This delays some modules in order to accelerate others. To exhibit the significance of simultaneously considering both kinematic and dynamics bounds, we consider the following "x-axis to y-axis" reconfiguration problem. Given a horizontal row of n modules, reconfigure that collection into a vertical column of n modules. The goal is to determine the sequence of movements of the modules that minimizes the movement time needed to achieve the desired reconfiguration of the modules. In this work we prove tight [Formula: see text] upper and lower bounds on the movement time for the above reconfiguration problem. Prior work on reconfiguration problems which focused only on kinematic constraints kept a constant velocity bound on individual modules and so required time linear in n to complete problems of this type.

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22

Cabral, Matheus M., Sofia A. Lemes, Marcelo E. de Oliveira, Paulo H. A. Silva e Silva, and Ghunter P. Viajante. "Software for calculating the optimum tilt angle of PV modules in different latitudes of the Southern hemisphere and solar plant sizing." Renewable Energy and Power Quality Journal 19 (September 2021): 304–9. http://dx.doi.org/10.24084/repqj19.282.

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Through the development of photovoltaic technologies, the market related to this type of renewable energy grows constantly. In Brazil, the generated power through photovoltaic (PV) power stations approximates to 2.3 GW representing 1.3% of the total Brazilian energy mix. To supply the public it is necessary to offer tools that facilitate consumer decision making or even the work of a solar farm designer. By analyzing the user’s necessity, it is possible to determine that a great parcel needs a quick and simple response to help them with their questions, and programs that are already well established in the marketplace are complex for inexperienced users. For this reason, a software that calculates the best inclination for PV modules using the method proposed by Liu and Jordan in 1962 is developed. It also determines the number of modules that can be installed without any shading between arrays within a user-defined area. This calculation is possible through the standard dimensions provided by the module manufacturers and the solar height and declination study. Through a simple interface, the user quickly receives the optimum tilt angle of installation, the number of PV modules and the maximum generated power.

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23

Gubler, M., D. Braguglia, J. Meyer, A. Piekarowicz, and T. A. Bickle. "Recombination of constant and variable modules alters DNA sequence recognition by type IC restriction-modification enzymes." EMBO Journal 11, no. 1 (January 1992): 233–40. http://dx.doi.org/10.1002/j.1460-2075.1992.tb05046.x.

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24

Ballardini, Mario, Fabio Finelli, and Domenico Sapone. "Cosmological constraints on the gravitational constant." Journal of Cosmology and Astroparticle Physics 2022, no. 06 (June 1, 2022): 004. http://dx.doi.org/10.1088/1475-7516/2022/06/004.

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Abstract We study the variation of the gravitational constant on cosmological scales in scalar-tensor theories of gravity. We focus on the simplest models of scalar-tensor theories with a coupling to the Ricci scalar of the form F(σ) = N 2 pl + ξσ 2, such as extended Jordan-Brans-Dicke (N pl = 0), or a non-minimally coupled scalar field with N pl = M pl, which permits the gravitational constant to vary self-consistently in time and space. In addition, we allow the effective gravitational constant on cosmological scales to differ from the Newton's measured constant G, i.e. G eff(z = 0) = G(1+Δ)2. We study the impact of this imbalance Δ jointly with the coupling ξ into anisotropies of the cosmic microwave background and matter power spectrum at low-redshift. Combining the information from Planck 2018 CMB temperature, polarization and lensing, together with a compilation of BAO measurements from the release DR12 of the Baryon Oscillation Spectroscopic Survey (BOSS), we constrain the imbalance to Δ = -0.022 ± 0.023 (68% CL) and the coupling parameter to 103 ξ < 0.82 (95% CL) for Jordan-Brans-Dicke and for a non-minimally coupled scalar field with F(σ) = M 2 pl + ξσ 2 we constrain the imbalance to Δ > -0.018 (< 0.021) and the coupling parameter to ξ < 0.089 (ξ > - 0.041) both at 95% CL. With current data, we observe that the degeneracy between Δ, the coupling ξ to the Ricci scalar, and H 0 allows for a larger value of the Hubble constant increasing the consistency between the distance-ladder measurement of the Hubble constant from supernovae type Ia by the SH0ES team and its value inferred by CMB data. We also study how future cosmological observations can constrain the gravitational Newton's constant. Future data such as the combination of CMB anisotropies from LiteBIRD and CMB-S4, and large-scale structures galaxy clustering from DESI and galaxy shear from LSST reduce the uncertainty in Δ to σ(Δ) ≃ 0.004.

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25

Hung, San Shan, Hsing Cheng Chang, and Chan Ming Liang. "Design of the Liquid-Cooling System for High Power LED Modules Using Taguchi Analysis." Advanced Materials Research 383-390 (November 2011): 6416–21. http://dx.doi.org/10.4028/www.scientific.net/amr.383-390.6416.

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To optimize thermal dissipation efficiency for cooling high power LED modules is studied and analyzed using ANSYS CFX software and Taguchi method. In liquid-cooling system, four control factors are tested and compared in order to find the best cooling arrangement that are pump flow rate, fan power, cooling liquid type and k- value of thermal compound. The experimental results show that the importance of these cooling parameters applied to high power LED module are k-value of thermal compound, fan power, liquid type and pump flow rate in sequence. For a constant heating power of 90W from an LED lighting module, an optimal thermal resistance of 0.563K/W is obtained that shows a significant improved result then the conventional LED module’s. It has high potential in future high power LED applications.

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26

Boulad, Natalia, Sattam Al Shogoor, Wahib Sahwan, Nedal Al-Ouran, and Brigitta Schütt. "Systematic Conservation Planning as a Tool for the Assessment of Protected Areas Network in Jordan." Land 11, no. 1 (December 31, 2021): 56. http://dx.doi.org/10.3390/land11010056.

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The present study aims to use systematic conservation planning to analyse and review the national protected areas (PAs) network in Jordan. The analysis included the application of three modules: the environmental risk surface (ERS), the relative biodiversity index (RBI), and the application of Marxan. The methodology was based on using Marxan to achieve solutions for three scenarios for the PAs network. Marxan was applied to the input data, which included vegetation types, distribution of threatened mammals and plants, locations of currently established PAs and other types of designations. The first two scenarios aimed to conserve 4% and 17%, respectively, of each vegetation type, and 10% and 20%, respectively, of the extent of occurrence of threatened mammals and plants. The third scenario aimed to conserve 17% of each vegetation type and 10% of the extent of occurrence of threatened plants and mammals, except for forest and the Hammada vegetation which had the target of 30% and 4%, respectively. The results of the three scenarios indicated that the boundaries of existing reserves should be extended to achieve the conservation targets. Some currently proposed (PAs), such as the Aqaba Mountains, did not appear in any of the solutions for the three scenarios indicating that the inclusion of these sites in the proposed (PAs) network should be reconsidered. All three scenarios highlighted the importance of having conservation areas between the western and eastern parts of the country. Systematic conservation planning is a structured, replicable, transparent, and defensible method for designing PA networks. It allows for finding efficient solutions building on what is currently conserved and minimizing the fragmentation and cost of the proposed solution for conservation areas.

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27

Muchie, Zelalem. "THE FALSE PROMISE OF COOPERATION IN THE JORDAN RIVER: STATE POLICIES AND DETERMINANTS." RUDN Journal of Political Science 21, no. 2 (December 15, 2019): 295–310. http://dx.doi.org/10.22363/2313-1438-2019-21-2-295-310.

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The study examines the false promise of cooperation in the Jordan River basin through the prism of state policies and determinants. The study is underpinned by the significance of pivotal riparian states. Based on their preeminence in determining the course of cooperation, the study considers Israel, Jordan and Palestine as pivotal riparian states. In terms of research methodology, qualitative approach was used. The study identified that domestic politics, regional dynamics and international water regimes are major determinant factors making cooperation to be a fantasy. Israel’s doctrine of exceptionalism both in the sense of statehood and government type and the reciprocated denial of co-basin states in this regard are domestic political factors that impede the course cooperative events. Israel’s geopolitical calculations via territorial expansion alongside of the Jordan River affect the cooperative milieu. The mere existence of water regimes either in the form of legal agreements or institutional attempts, does not bring effective cooperation. The finding of study shows that, domestic politics, regional dynamics and international water regimes are indeed determinant factors for the cooperative and conflictive nature of water sharing in the basin. The level of their impact however is neither equal nor constant. Importantly, these three factors affect and condition one another.

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28

Dmitrikov, Vladimir F., Alexander Yu Petrochenko, and Andrey A. Rozanov. "Design features of negative feedback and power smoothing filter of the DC / DC converter with pulse loads for transmitter-receiver modules of active electronically scanned arrays." Physics of Wave Processes and Radio Systems 24, no. 1 (May 6, 2021): 78–88. http://dx.doi.org/10.18469/1810-3189.2021.24.1.78-88.

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The fundamental difference of the voltage converter of the secondary power supply source for the transmitter-receiver modules of active electronically scanned arrays with impulse load and variable duty cycle from traditional voltage converters that constantly consume power from the primary network is shown. Methods for improving the quality of transient processes in voltage converter with constant power consumption during start-up by soft start are not applicable to improve the quality of transients in periodic current pulses caused by a pulsed load. Since any ripples, noises, instabilities in the power supply of the transmitter-receiver modules of active electronically scanned arrays operating in a linear mode lead to parasitic amplitude modulation of the emitted signal and to a deterioration in the quality of selection and target tracking, very strict requirements are imposed on the quality of the transmitter-receiver modules supply voltage (voltage ripple kп 0,5 %, the amount of overshoot of the output voltage sU 2 %, etc.). The article shows that such a quality of the output voltage with a pulsed load of the transmitter-receiver modules of active electronically scanned arrays can be obtained using a lower-type voltage converter, with a double-circuit negative feedback for the output voltage and current of the inductor, with a storage capacitor and with a power smoothing filter with the characteristics of Chebyshev and Butterworth. The work investigated the influence of the negative feedback depth on the output voltage and current of the smoothing filter choke, the value of the storage capacitor capacity, the type and parameters of the smoothing filter, and recommendations were given to select their optimal values, at which the required quality of the supply voltage for the transmitter-receiver modules of active electronically scanned arrays was ensured, taking into account the minimization of their dimensions.

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29

Hosseini, Seyed Saeid, Javad Aminian Dehkordi, and Prodip K. Kundu. "Mathematical Modeling and Investigation on the Temperature and Pressure Dependency of Permeation and Membrane Separation Performance for Natural gas Treatment." Chemical Product and Process Modeling 11, no. 1 (March 1, 2016): 7–10. http://dx.doi.org/10.1515/cppm-2015-0051.

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Abstract Due to special features, modules comprising asymmetric hollow fiber membranes are widely used in various industrial gas separation processes. Accordingly, numerous mathematical models have been proposed for predicting and analyzing the performance. However, majority of the proposed models for this purpose assume that membrane permeance remains constant upon changes in temperature and pressure. In this study, a mathematical model is proposed by taking into account non-ideal effects including changes in pressure and temperature in both sides of hollow fibers, concentration polarization and Joule-Thomson effects. Finite element method is employed to solve the governing equations and model is validated using experimental data. The effect of temperature and pressure dependency of permeance and separation performance of hollow fiber membrane modules is investigated in the case of CO2/CH4. The effect of temperature and pressure dependence of membrane permeance is studied by using type Arrhenius type and partial immobilization equations to understand which form of the equations fits experimental data best. Findings reveal that the prediction of membrane performance for CO2/CH4 separation is highly related to pressure and temperature; the models considering temperature and pressure dependence of membrane permeance match experimental data with higher accuracy. Also, results suggest that partial immobilization model represents a better prediction to the experimental data than Arrhenius type equation.

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30

Santhosh Baboo, S., and Nikhil Lobo. "Thinking Outside Conventional Aerospace and Defense Technical Publications Using Standard Generalized Markup Language (SGML)." Open Aerospace Engineering Journal 2, no. 1 (October 16, 2009): 19–27. http://dx.doi.org/10.2174/1874146000902010019.

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In Aerospace and Defense, documentation is of a very large size, highly structured and needs constant updating. Managing this documentation has been a constant challenge to this industry. Moreover accuracy of data is a critical aspect of constant worry to publication managers. At present, documentation is being created using traditional publishing software resulting in wastage of time and effort. Time is spent in formatting documents instead of creation of content. Each time a document is created or updated formatting has to be applied manually. Preparing documents for print or web requires complete reformatting. Content is not structured across similar types of publications resulting in no consistency. Standard Generalized Mark-up Language (SGML) allows a document to be broken up into modules allowing reusability. SGML enforces content to be developed in a structured manner maintaining consistency across publications. This structured approach is achieved using a Document Type Definition (DTD). Separation of content from formatting is achieved using Format Output Specification Instance (FOSI).

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31

Zarybnicka, Lucie, Karel Dvorak, Zdenka Dostalova, and Hana Vojackova. "Study of Different Printing Design Type Polymer Samples Prepared by Additive Manufacturing." Periodica Polytechnica Chemical Engineering 64, no. 2 (October 10, 2019): 255–64. http://dx.doi.org/10.3311/ppch.13991.

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3D printing is one of the most progressive additive technologies today. It finds its application also in industry. In terms of mechanical properties, the printing design of the product is an important parameter. The presented study investigates the effects of the printing design of a thin-walled 3D polymer model on the mechanical properties of the model. The material used for printing was acrylonitrile-butadiene-styrene (ABS) and the 3D print method was Fused Deposition Modeling (FDM). ABS was tested at various die temperatures and with various printing designs at a constant 3D print speed and identical print bed temperature. We examined the effect of printing temperature and product printing design on the resulting mechanical properties. We compared theoretical and experimental results by CAE–FEM Advanced Simulation modules. Results tensile deformations at maximum load by experiment and simulations are comparable. The best results of testing the mechanical properties were found in the pattern printed at a 45° angle at temperature 285 °C.

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32

Dobrzycki, Arkadiusz, Dariusz Kurz, and Ewa Maćkowiak. "Influence of Selected Working Conditions on Electricity Generation in Bifacial Photovoltaic Modules in Polish Climatic Conditions." Energies 14, no. 16 (August 13, 2021): 4964. http://dx.doi.org/10.3390/en14164964.

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This paper discusses the conversion of solar irradiance energy into electricity. Double-sided (bifacial) panels are gaining increasing popularity in commercial applications due to the increased energy yield with a constant occupied mounting surface. However, the value of the additional energy yield produced by the back of the panel depends on several important factors. This paper presents the influence of working conditions on electricity generation in bifacial modules. This paper also investigates the influence of weather conditions, the module inclination angle, and the substrate beneath the panel surface on electricity generation. Fill factor and efficiency were calculated for each case included in the study scope. Based on the current voltage, power characteristics, and calculations, the module operation for different conditions was compared. It was observed that the optimal inclination angle to the surface is higher for the bifacial modules compared to the unilateral modules. The type of surface under the module has also been indicated to impact the amount of electricity generated. The additional energy yield associated with the panels’ rear side accounts for 2% to more than 35% of the total power generated by a photovoltaic (PV) module. The unit cost of electricity generation in the analyzed cases was also determined.

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33

Sahu, Preeti Kumari, J. N. Roy, Chandan Chakraborty, and Senthilarasu Sundaram. "A New Model for Estimation of Energy Extraction from Bifacial Photovoltaic Modules." Energies 14, no. 16 (August 18, 2021): 5089. http://dx.doi.org/10.3390/en14165089.

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The energy yield from bifacial solar photovoltaic (PV) systems can be enhanced by optimizing the tilt angle. Bifacial modules boost the energy yield by 4% to 15% depending on the module type and ground reflectivity with an average of 9%. The selection of tilt angle depends on several factors, including the geographical location, weather variation, etc. Compared to the variable tilt angle, a constant angle is preferred from the point of view of the cost of installation and the cost of maintenance. This paper proposes a new method for analysing bifacial modules. A simpler rear-side irradiance model is presented to estimate the energy yield of a bifacial solar photovoltaic module. The detailed analysis also explores the optimum tilt angle for the inclined south–north orientation to obtain the maximum possible yield from the module. Taking four regions into account, i.e., Kharagpur, Ahmedabad, Delhi, and Thiruvananthapuram, in the Indian climate, we studied several cases. The Kharagpur system showed a monthly rear irradiance gain of 13%, and the Delhi climate showed an average performance ratio of 19.5%. We studied the impact of albedo and GCR on the tilt angle. Finally, the estimated model was validated with the PVSyst version 6.7.6 as well as real field test measurements taken from the National Renewable Energy Laboratory (NREL) located in the USA.

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34

Ruus, Viive-Riina, and Inge Timoštšuk. "SEARCHING FOR CONSTANT INNOVATION IN TEACHER EDUCATION CURRICULA: THE CASE OF ESTONIA." Problems of Education in the 21st Century 62, no. 1 (December 15, 2014): 97–108. http://dx.doi.org/10.33225/pec/14.62.97.

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The study addresses the tensions between the aims and objectives of global, national and local curricula and suggests solutions for mitigating these conflicts using the experience of Estonia as an example. In spite of the success of recent reforms and the good results of students in international comparisons, there are serious deficiencies: an Estonian teacher’s readiness to use professional freedom is modest, personal efficiency, job satisfaction, and students’ motivation to learn is low: there are few outstanding performers. The aim of the study is to propose and analyse a teacher education curriculum innovation model for overcoming the problem. Adaptive model for curriculum design is presented where the predominant outcome-oriented approach was replaced and focus on teaching and learning processes was highlighted, the logic of design in curriculum development was implemented. A model for the practice component of teacher education, based on Wenger`s situated learning model and Engeström’s expansive learning model, is in the focus. It is found that implementing this approach could encourage a development of standards and transform the attitudes of both students and teachers towards increased creativity and professional development. The implementation of the described curriculum innovation model enhances new type of learning and can generate new modules in teacher education curricula. Key words: adaptive competence, curriculum design, Estonian education, practice in teacher education.

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Syayakti, Syafiq Naufal, Endang Dian Setioningsih, and Sumber Sumber. "4 Channel Sterilizer Calibrator." Indonesian Journal of electronics, electromedical engineering, and medical informatics 1, no. 2 (February 5, 2020): 65–70. http://dx.doi.org/10.35882/ijeeemi.v1i2.4.

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Thermocouple (Thermocouple) is a type of temperature sensor used to detect or measure temperature through two types of metal conductors, whose working principle is that each end of a metal conductor is combined to create a "Thermoelectric" effect. One type of metal conductor contained in a thermocouple will serve as a reference with a constant temperature (fixed), while a metal conductor functions as a metal conductor that detects hot temperatures. Sterilisator is a device used to sterilize medical instruments to avoid the bacteria that attach to the remainder of the use of medical instruments. The temperature of the sterilizer varies but generally for dry sterilizers ranges from 175 ° Celsius. From the above problems, the author wants to develop a "4 Channel Sterilizer Calibrator", Using the Arduino Nano Atmega328 as a minimum system, K type thermocouple and MAX6675 module as a sensor. Measurements were made by comparing modules with standard measuring instruments, obtained the smallest error 0.2% at T3 and T4 when measuring 100 ° C, and the largest 4.4% at T2 when measuring 150 ° C.

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Anderson Azzano, Jorge Luis, Jerónimo J. Moré, and Paul F. Puleston. "Stability Criteria for Input Filter Design in Converters with CPL: Applications in Sliding Mode Controlled Power Systems." Energies 12, no. 21 (October 24, 2019): 4048. http://dx.doi.org/10.3390/en12214048.

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Microgrids are versatile systems for integration of renewable energy sources and non-conventional storage devices. Sliding Mode techniques grant excellent features of robustness controlling power conditioning systems, making them highly suitable for microgrid applications. However, problems may arise when a converter is set to behave as a Constant Power Load (CPL). These issues manifest in the stability of internal dynamics (or Zero Dynamics), which is determined by the input filter of the power module. In this paper, a special Lyapunov analysis is conducted to address the nonlinear internal dynamics of SM controlled power modules with CPL. It takes advantage of a Liérnad-type description, establishing stability conditions and providing a secure operation region. These conditions are translated into conductance and invariant region diagrams, turning them into tools for the design of power module filters.

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37

Sirisha, Bogimi, and Mohd Abdul Nazeemuddin. "A novel five-level voltage source inverter interconnected to grid with srf controller for voltage synchronization." Bulletin of Electrical Engineering and Informatics 11, no. 1 (February 1, 2022): 50–58. http://dx.doi.org/10.11591/eei.v11i1.3274.

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Power utilization from renewable sources with efficient modules is very vital. Maitaining harmonics below specific standard during grid interconnection is also a major objective. A novel five-level voltage source inverter which is controlled by synchronous reference frame (SRF) controller for grid interconnection and synchronized power injection. The input of the converter is integrated with renewable energy source photovoltaic arrays (PVA) for the injection of renewable power into the grid. For constant voltage input, the PVAs are connected to a booster converter controlled by the maximum power point tracking (MPPT) algorithm. The design is analyzed with different operating conditions by changing the load type (static and dynamic) using MATLAB/Simulink software. Graphical comparisons are taken for the analysis with the help of ‘powergui’ toolbox available in the software.

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Marschalek, R., J. Hofmann, G. Schumann, R. Gösseringer, and T. Dingermann. "Structure of DRE, a retrotransposable element which integrates with position specificity upstream of Dictyostelium discoideum tRNA genes." Molecular and Cellular Biology 12, no. 1 (January 1992): 229–39. http://dx.doi.org/10.1128/mcb.12.1.229.

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Different Dictyostelium discoideum strains contain between 2 and 200 copies of a retrotransposable element termed DRE (Dictyostelium repetitive element). From the analysis of more than 50 elements, it can be concluded that DRE elements always occur 50 +/- 3 nucleotides upstream of tRNA genes. All analyzed clones contain DRE in a constant orientation relative to the tRNA gene, implying orientation specificity as well as position specificity. DRE contains two open reading frames which are flanked by nonidentical terminal repeats. Long terminal repeats (LTRs) are composed of three distinct modules, called A, B, and C. The tRNA gene-proximal LTR is characterized by one or multiple A modules followed by a single B module (AnB). With respect to the distal LTR, two different subforms of DRE have been isolated. The majority of isolated clones contains a distal LTR composed of a B module followed by a C module (BC), whereas the distal LTR of the other subform contains a consecutive array of a B module, a C module, a slightly altered A module, another B module, and another C module (BC.ABC). Full-length as well as smaller transcripts from DRE elements have been detected, but in comparison with the high copy number in D. discoideum strains derived from the wild-type strain NC4, transcription is rather poor.

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39

Marschalek, R., J. Hofmann, G. Schumann, R. Gösseringer, and T. Dingermann. "Structure of DRE, a retrotransposable element which integrates with position specificity upstream of Dictyostelium discoideum tRNA genes." Molecular and Cellular Biology 12, no. 1 (January 1992): 229–39. http://dx.doi.org/10.1128/mcb.12.1.229-239.1992.

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Анотація:

Different Dictyostelium discoideum strains contain between 2 and 200 copies of a retrotransposable element termed DRE (Dictyostelium repetitive element). From the analysis of more than 50 elements, it can be concluded that DRE elements always occur 50 +/- 3 nucleotides upstream of tRNA genes. All analyzed clones contain DRE in a constant orientation relative to the tRNA gene, implying orientation specificity as well as position specificity. DRE contains two open reading frames which are flanked by nonidentical terminal repeats. Long terminal repeats (LTRs) are composed of three distinct modules, called A, B, and C. The tRNA gene-proximal LTR is characterized by one or multiple A modules followed by a single B module (AnB). With respect to the distal LTR, two different subforms of DRE have been isolated. The majority of isolated clones contains a distal LTR composed of a B module followed by a C module (BC), whereas the distal LTR of the other subform contains a consecutive array of a B module, a C module, a slightly altered A module, another B module, and another C module (BC.ABC). Full-length as well as smaller transcripts from DRE elements have been detected, but in comparison with the high copy number in D. discoideum strains derived from the wild-type strain NC4, transcription is rather poor.

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40

Fernández Cristóbal, José Ma. "Weyl invariance in metric f(R) gravity." Revista Mexicana de Física 64, no. 2 (March 14, 2018): 181. http://dx.doi.org/10.31349/revmexfis.64.181.

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We aim to derive the most general f(R) gravity theory, including thematter, so that it be Weyl invariant. Making use of the mathematicalequivalence of these theories with an type of scalar-tensor theory, and byimposing the Weyl invariance for the pure gravity as well as for the mattersector, we obtain the fundamental equation that restricts the form of V (phi) (and, accordingly, of f(R)) so that the resulting action to be Weylinvariant in the Jordan frame. We show that this action is not otherthan the so-called dilaton gravity action with one scalar eld,, whicheective mass is R and Phi dependent. In the Einstein frame, the actionbecomes the Einstein-Hilbert action with the Ricci scalar being constantdue to that the eective mass of scalar eld in this frame vanish. So,we can assume that the Ricci scalar, in the Einstein frame, is the trueCosmological Constant. Therefore, is not preposterous to guess that, atleast mathematically, all Weyl invariant metric f(R) theory in the Jordanframe is equivalent, at classical level, to the Einstein gravity, in theEinstein frame, with a constant Ricci scalar. At quantum level, as it isknown, both theories are not equivalent due to the presence of anomaliesin one of the frames.

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GEORGIADES, G., and S. O. OYADIJI. "PERFORMANCE OF PIN ELECTRODE ER VALVES." International Journal of Modern Physics B 19, no. 07n09 (April 10, 2005): 1668–74. http://dx.doi.org/10.1142/s0217979205030748.

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This work concentrates on the development of an uncommon type of electrodes to be used in electrorheological devices. Rather than using electrodes with constant gap, pin electrodes are used, in order to achieve variation in the gap. The device described has pins running across the direction of the flow. The ER fluid moves through rows and columns of pin electrodes of different polarities. One of the main problems would be the development of the head pressure drop as the number of rows of pins increases. The work presents different configurations that could be constructed using pin electrodes. One of the configurations is developed and tested as to the pressure gradients that could be achieved when different magnitudes of electric potentials are applied. The results are compared to the ones obtained when two of the constructed modules are aligned one after the other for the tests.

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Kim, Ju Won, Eun Seok Shin, Chang Gil Lee, Seung Hee Park, and Seo Kinn Hong. "Curing Strength Monitoring of Early-Age Concrete Based on Velocity of Guided Wave Using Embedded Plate-Type PZT Sensor Module." Applied Mechanics and Materials 281 (January 2013): 645–48. http://dx.doi.org/10.4028/www.scientific.net/amm.281.645.

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In this study, a guided wave based nondestructive curing strength monitoring method is proposed to monitor the curing strength of the early-age concrete. This approach used the embedded steel plate-type PZT sensor module which was fabricated by bonding the two pieces of piezoelectric sensor to a steel plate. The steel plate provided the constant path for guided wave propagation and it protected the piezoelectric sensors from impacts and environmental variations. To measure the guided wave signals from the early-age concrete, fabricated sensor modules were landfilled at the same time with concrete placement.While the concrete was curing, guided wave signals were measured by pitch-catch method continuously at regular intervals. Wavelet transform process was performed to improve the quality of the signal by removing the signal’s noise of undesired frequencies. The TOF (Time of flight) of guidedwave was extract from de-noised signal using peak tracing algorithm to calculate the velocity of wave. The calculated wave velocity hysteresis according to the curing time was traced to analysis the pattern of variations of wave velocity. Finally, specific equations to estimate the strength of the concrete were derived using regression analysis based on the wave velocity and compressive strength from destructive compressive strength test.

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Kowalska, Magdalena. "Influence of Loading History and Boundary Conditions on Parameters of Soil Constitutive Models." Studia Geotechnica et Mechanica 34, no. 1 (March 1, 2012): 15–33. http://dx.doi.org/10.1515/sgem-2017-0020.

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Abstract Parameters of soil constitutive models are not constant. This mainly concerns the strain parameters such as K, G or Eoed modules. What influences their values is not only soil type, structure and consistency, but also the history of stress and strain states. So, it is the question of the current state but also of what happened to the subsoil in the past (regarding geological and anthropological activity) and what impact would have the planned soil–structure interaction. This paper presents an overview of the literature showing how much the soil constitutive model parameters depend on loading and boundary conditions of a particular geotechnical problem. Model calibration methods are shortly described with special attention paid to the author’s “Loading Path Method”, which allows estimation of optimum parameter values of any soil constitutive model. An example of the use of this method to estimate strain parameters E and ν of Coulomb–Mohr elasticperfectly plastic model is given.

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Caradonna, Salvatore G., Tie-Yuan Zhang, Nicholas O’Toole, Mo-Jun Shen, Huzefa Khalil, Nathan R. Einhorn, Xianglan Wen, et al. "Genomic modules and intramodular network concordance in susceptible and resilient male mice across models of stress." Neuropsychopharmacology 47, no. 5 (November 30, 2021): 987–99. http://dx.doi.org/10.1038/s41386-021-01219-8.

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AbstractThe multifactorial etiology of stress-related disorders necessitates a constant interrogation of the molecular convergences in preclinical models of stress that use disparate paradigms as stressors spanning from environmental challenges to genetic predisposition to hormonal signaling. Using RNA-sequencing, we investigated the genomic signatures in the ventral hippocampus common to mouse models of stress. Chronic oral corticosterone (CORT) induced increased anxiety- and depression-like behavior in wild-type male mice and male mice heterozygous for the gene coding for brain-derived neurotrophic factor Val66Met, a variant associated with genetic susceptibility to stress. In a separate set of male mice, chronic social defeat stress (CSDS) led to a susceptible or a resilient population, whose proportion was dependent on housing conditions, namely standard housing or enriched environment. Rank-rank-hypergeometric overlap (RRHO), a threshold-free approach that ranks genes by their p value and effect size direction, was used to identify genes from a continuous gradient of significancy that were concordant across groups. In mice treated with CORT and in standard-housed susceptible mice, differentially expressed genes (DEGs) were concordant for gene networks involved in neurotransmission, cytoskeleton function, and vascularization. Weighted gene co-expression analysis generated 54 gene hub modules and revealed two modules in which both CORT and CSDS-induced enrichment in DEGs, whose function was concordant with the RRHO predictions, and correlated with behavioral resilience or susceptibility. These data showed transcriptional concordance across models in which the stress coping depends upon hormonal, environmental, or genetic factors revealing common genomic drivers that embody the multifaceted nature of stress-related disorders.

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Mizeret, Jérôme, Nathalie Nyffeler, Sylvie Ray-Kaeser, Noémie Délèze, and Mélanie Thomas. "Case study: the contributions of a FabLab to a Bachelor cursus in Occupational Therapy." ITM Web of Conferences 41 (2022): 03003. http://dx.doi.org/10.1051/itmconf/20224103003.

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The aim of this research is to explore the contributions of FabLabs in applied tertiary education (Bachelor University of Applied Sciences – UAS), and particularly in the form of hybrid teaching modules, combining academic subjects and maker experience. FabLabs can offer services to the professors of various academic fields to reinvent their teaching methodologies, incorporating making as a way to transmit knowledge and enhance student engagement. We have also established with higher education professors and lecturers in mind, the conditions for the implementation of such modules in order to guarantee their success. A pilot project has been conducted with occupational therapy students consisting of a one-semester module of 30 periods, dedicated to developing and prototyping in order to adapt toys and games to be used by children with cerebral palsy of the spastic hemiplegia type. The FabLab was the place where prototypes were made, but also where exchange, collaboration and creativity were catalysed. Our observations showed that the students developed three types of skills: technical (use of digital 3D CAD software and machines), occupational, in the field of occupational therapy (observation and analysis of the accessibility of the environment, solution-oriented approach aimed at increasing occupational performance and participation) and relational (creativity, agility, collaboration). Commitment and pleasure of learning were present throughout the module. The conditions for the success were the co-construction of the learning experience by both the professors and the labmanagers in charge of the FabLab, the establishment of a pedagogical scenario, and constant, open communication between them.

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46

Panea, Crina, Ioan Felea, and Ioan Almăşan. "The Simulation of Processes and Performances within Low Enthalpy Geothermal Power Plants." Advanced Materials Research 875-877 (February 2014): 1647–53. http://dx.doi.org/10.4028/www.scientific.net/amr.875-877.1647.

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On the perspective of constant development, a major objective of today’s international strategies – the exploitation of nonpolluting resources becomes a very important aspect. Geothermal energy represents one of the renewable energy resources. The exploitation of geothermal resources of low enthalpy with the aim of producing electric energy is a well extended direction of development. The paper is dedicated to the simulation of processes and performances within equipments which build up a GPP having as a destination the exploitation of low enthalpy geothermal deposits. After the short presentation of the actuality subject and the structure of GPP we pass on to the draft modules for the equipments from the GPP structure, with the aim of specific processes simulation. By using the programming medium Matlab/Simulink we apply the model for a GPP which will function according to pre-established conditions. The obtained result after simulation are verry good, and the most important parameter wich is followed is the efficiency of the plant. The results for this parameter is high for this type of power plants.

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Yurkov, R. S., and L. I. Knysh. "Verification of a mathematical model for the solution of the Stefan problem using the mushy layer method." Technical mechanics 2021, no. 3 (October 12, 2021): 119–25. http://dx.doi.org/10.15407/itm2021.03.119.

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The use of solar energy has limitations due to its periodic availability: solar plants do not operate at night and are ineffective in dull weather. The solution of this problem involves the introduction of energy storage and duplication systems into the conversion loop. Among the energy storage systems, solid–liquid phase transition modules have significant energy, ecologic, and cost advantages. Physical processes in modules of this type are described by a system of non-stationary nonlinear partial differential equations with specific boundary conditions at the phase interface. The verification of a method for solving the Stefan problem for a heat-storage material is presented in this paper. The use of the mushy layer method made it possible to simplify the classical mathematical model of the Stefan problem by reducing it to a nonstationary heat conduction problem with an implicit heat source that takes into account the latent heat of transition. The phase transition is considered to occur in an intermediate zone determined by the solidus and liquidus temperatures rather than in in infinite region. To develop a Python code, use was made of an implicit computational scheme in which the solidus and liquidus temperatures remain constant and are determined in the course of numerical experiments. The physical model chosen for computer simulation and algorithm verification is the process of ice layer formation on a water surface at a constant ambient temperature. The numerical results obtained allow one to determine the temperature fields in the solid and the liquid phase and the position of the phase interface and calculate its advance speed. The algorithm developed was verified by analyzing the classical analytical solution of the Stefan problem for the one-dimensional case at a constant advance speed of the phase interface. The value of the verification coefficient was determined from a numerical solution of a nonlinear equation with the use of special built-in Python functions. Substituting the data for the physical model under consideration into the analytical solution and comparing them with the numerical simulation data obtained with the use of the mushy layer method shows that the results are in close agreement, thus demonstrating the correctness of the computer algorithm developed. These studies will allow one to adapt the Python code developed on the basis of the mushy layer method to the calculation of heat storage systems with a solid-liquid phase transition with account for the features of their geometry, the temperature level, and actual boundary conditions.

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Jeon, Yuseok, and Byeongchang Kim. "Design of a 0.5–18 GHz Wideband Frequency Down-Converter Module with a Local Circuit for an Electronic Support Measurement System." Journal of Electromagnetic Engineering and Science 22, no. 2 (March 31, 2022): 103–13. http://dx.doi.org/10.26866/jees.2022.2.r.66.

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In this paper, we describe the design and fabrication of a wideband frequency down converter module that has a local circuit with high gain, low spurious, high IP3 (3rd intercept point) characteristics, and reliability; this is accomplished by applying a chip-and-wire process using a bare type monolithic microwave integrated circuit (MMIC) device. To compensate for the mismatch among many sub-modules, an input module, filter bank module, output module, and local oscillator (LO) module suitable for sub-band frequency characteristics were designed and applied to the down converter. Th e frequency down converter module had three paths: 0.5−2 GHz (direct), 2−6 GHz (direct), and 6−18 GHz (converter). Amplitude-matched radio frequency (RF) semi-rigid cables of different lengths were used to connect to the internal sub-modules of the frequency down converter. The main RF line was a dielectric substrate, RT/duroid 5880, with a relative dielectric constant of 2.2 and a dielectric thickness of 0.127 mm. In the wideband frequency down converter module, the gain was 22.7 dB at low band (input frequency, 0.5−2 GHz) with a flatness of about 3.4 dB. Th e gain was 22.6 dB at mid band (input frequency, 2−6 GHz) having flatness about 2.0 dB. The gain was from 30 dB at edge frequency of high band (input frequency, 14−18 GHz) with a flatness of about 4.2 dB. The measured value of IP3 at LB was +23.52 dBm, +25.66 dBm and +23.44 dBm as the maximum value. The measured value of spurious (LO-2IF) at the converter path was 34.97 dBc as the maximum value.

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Yu, Ming, Wenwen Liu, Jian Zhao, Yanyan Hou, Xuewu Hong, and Hongjie Zhang. "Modeling and Analysis of a Composite Structure-Based Soft Pneumatic Actuators for Soft-Robotic Gripper." Sensors 22, no. 13 (June 27, 2022): 4851. http://dx.doi.org/10.3390/s22134851.

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Soft pneumatic actuators are extensively used in soft robots, and their bending angles and kinematic rules at different pressures play a crucial role in practical applications. This investigation aims to model the bending angle and motion of a new type of soft pneumatic actuator that adopts a composite structure consisting of two kinds of pneumatic networks. Based on the structural and deformation characteristics of the proposed soft actuator, the constitutive model is established, and then the moment equilibrium and virtual work principle are combined to model the bending angle of two pneumatic modules. The kinematic model of the proposed soft actuator is co-opted from the kinematic modeling of rigid robots. By employing the piecewise constant curvature method and coordinate transformation, the location of any chamber of the soft actuator can be calculated. The effectiveness of the developed analytical models is then tested, and the calculated results show good agreement with the experimental results. Finally, three soft actuators are used to constitute a soft gripper, and the pinching and enveloping grasping performance are examined. All experimental test results demonstrate that the developed bending angle and kinematic models can explain the bending principle of the proposed soft actuators well.

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Dehkordi, Javad Aminian, Seyed Saeid Hosseini, Prodip K. Kundu, and Nicolas R. Tan. "Mathematical Modeling of Natural Gas Separation Using Hollow Fiber Membrane Modules by Application of Finite Element Method through Statistical Analysis." Chemical Product and Process Modeling 11, no. 1 (March 1, 2016): 11–15. http://dx.doi.org/10.1515/cppm-2015-0052.

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Abstract Hollow fiber membrane permeators used in the separation industry are proven as preferred modules representing various benefits and advantages to gas separation processes. In the present study, a mathematical model is proposed to predict the separation performance of natural gas using hollow fiber membrane modules. The model is used to perform sensitivity analysis to distinguish which process parameters influence the most and are necessary to be assessed appropriately. In this model, SRK equation was used to justify the nonideal behavior of gas mixtures and Joule-Thomson equation was employed to take into account the changes in the temperature due to permeation. Also, the changes in temperature along shell side was calculated via thermodynamic principles. In the proposed mathematical model, the temperature dependence of membrane permeance is justified by the Arrhenius-type equation. Furthermore, a surface mole fraction parameter is introduced to consider the effect of accumulation of less permeable component adjacent to the membrane surface in the feed side. The model is validated using experimental data. Central Composite Designs are used to gain response surface model. For this, fiber inner diameter, active fiber length, module diameter and number of fibers in the module are taken as the input variables related to the physical geometries. Results show that the number as well as the length of the fibers have the most influence on the membrane performance. The maximum mole fraction of CO2 in the permeate stream is observed for low number of fibers and fibers having smaller active lengths. Also results indicate that at constant active fiber length, increasing the number of fibers decreases the permeate mole fraction of CO2. The findings demonstrate the importance of considering appropriate physical geometries for designing hollow fiber membrane permeators for practical gas separation applications.

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