bluuebunny/crossref_metadata_2025 huggingface dataset:
The Language Diversity and Science Readiness Skills of Latino Preschoolers
Authors: Halpin Emily , Prishker Nydia , Melzi Gigliana
Published: December 2022

Purpose:

The purpose of this study was twofold: (a) to describe how the language diversity (i.e., the within-group variability in dual-language skills) of Latino dual-language learner (DLL) preschoolers was related to their science readiness skills and (b) to describe the importance of language of science instruction for Spanish-dominant children.

Method:

Latino DLL children's (
N
= 161; ages 3–5 years) language skills were assessed in various domains of both Spanish and English, and then their science readiness skills were assessed in their dominant language. Using a latent profile analysis, profiles were generated to describe the diversity of DLLs' bilingual skills. These profiles were used as independent variables in a series of hierarchical regressions to predict children's science readiness skills. With the Spanish-dominant subsample, an interaction term was created between profile membership and language of science instruction to determine how language of instruction contributes to the relation between language and science readiness skills.

Results:

English-dominant children and children with high and balanced dual-language skills had the highest science readiness skills, and instruction in two languages was related to higher science readiness skills of certain Spanish-dominant children. Results underscore the linguistic heterogeneity of Latino DLL children and its importance for school success and bilingual instruction initiatives.

Conclusion:

Findings provide evidence for the within-group variability in the dual-language skills of Latino DLL preschool children relating to differences in their science readiness skills, as well as for how bilingual instruction is related to science readiness skill.
Economic analysis of aluminium conductor composite core and conventional aluminium conductor steel reinforced conductors in overhead ultra‐high voltage transmission lines
Authors: Zhang Yujiao , Sun Hongda , Zhang Xuankun , Chen Zhiwei , Zhou Li , Huang Xiongfeng
Published: December 2022

The application potential of aluminium conductor composite core (ACCC) conductors in the 1000‐kV power transmission line project deserves to be investigated. Its economic evaluation is a contentious issue. This paper proposes a method for selecting the type of conductors based on the life cycle cost (LCC) of a transmission line, which includes the initial investments, operation costs, maintenance costs, failure costs, and discard costs. The mathematical model of electromagnetic loss differs due to the various operational circumstances surrounding a transmission line; therefore, a novel three‐dimensional electromagnetic–fluid–thermal coupling model based on the finite element method (FEM) was proposed. The simulation error of ACCC and aluminium conductor steel reinforced (ACSR) conductors is 2.56% and 0.5%, respectively, compared to the experimental value. Subsequently, the LCC model is applied in the economic analysis of a 1000‐kV transmission line, and the costs of ACCC conductors and ACSR conductors under different annual power load utilization hours are calculated. The results indicate that the overhead power transmission line with ACCC conductors saves at least 2 × 106 ¥/km compared with ACSR when annual utilization hours reach 3500 h; meanwhile, energy saving benefits are achieved.
Improved related‐tweakey rectangle attacks on round‐reduced Deoxys‐BC
Authors: Liu Jiamei , Tan Lin , Xu Hong
Published: December 2022

Deoxys‐BC is the internal tweakable block cipher of the authenticated encryption (AE) Deoxys family, in which Deoxys‐II is the primary choice for the use case of ‘Defence in depth’ among the portfolio of CAESAR competition. Improvements of the related‐tweakey rectangle attacks on round‐reduced Deoxys‐BC using the known distinguishers is focussed in this study. Under the new related‐key rectangle attack framework proposed by Dong et al. in EUROCRYPT 2022, we present three kinds of precomputed tables to further reduce the time complexity in the key‐recovery phase. In the related‐tweakey rectangle attack, the invalid quartets are filtered or the subtweakey candidates are obtained by lookup the precomputed tables without more computation. Based on the precomputed table technique, we improved the related‐tweakey rectangle attacks on 11‐round Deoxys‐BC‐256, 13‐round and 14‐round Deoxys‐BC‐384. Furthermore, we reduce the time complexity of the 13‐round related‐tweakey rectangle attack on Deoxys AE scheme Deoxys‐I‐256‐128 by a factor of 224 compared with the best previous attack.
Estimating non-common path aberrations with an adaptive coronagraph
Authors: Radhakrishnan V. M. , Keller C. U. , Doelman N. J. , Por E. H.
Published: December 2022

Context.The focal-plane contrast of exoplanet imagers is affected by non-common path aberrations (NCPAs) that the adaptive optics system cannot correct for because they occur after the wavefront has been measured. NCPA estimation is commonly based on the long-exposure science image. Phase retrieval algorithms are often used, and they mostly assume that the residual phase error right after the adaptive optics system and averaged over the integration time is zero. This assumption is not always correct, for instance when controlling the adaptive optics to maximize the focal-plane contrast at the location of an exoplanet, that is to say in an adaptive coronagraph. For such cases, we present a method to calculate the NCPA using the phase information derived from the wavefront sensor (WFS) data and the science focal-plane image.

Aims.We aim to accurately estimate the NCPA phase in the presence of (residual) atmospheric turbulence with a nonzero average wavefront. We then aim to take the NCPA into account in the adaptive coronagraph controller and achieve a higher contrast.

Methods.The WFS measures the wavefront throughout the integration time of the science image. We combine information from the recorded WFS phases to remove the effects of the nonzero average phase from the Point Spread Function (PSF) and to remove the effects of the residual turbulence averaging over time. Then we estimate the NCPA by applying a phase-diversity-based algorithm to the resulting images. Our method is currently limited to imagers with pupil-plane coronagraphs.

Results.We are able to recover the NCPA in an adaptive coronagraph setting with 0.01 radian RMS residuals and with a residual turbulence phase error of approximately 0.4 radian RMS. When accounted for in a contrast-control scheme, the NCPA correction leads to an order of magnitude improvement of contrast and a 50% increase in Strehl ratio, in numerical simulations.
Research on emissions from large combustion plants (LCP). Case Study
Authors: Hrișcan Romeo , Kovacs Marius , Simion Sorin
Published: December 2022

According to Directive 2010/75 / EU and Law 278/2013 on industrial emissions, operators of large combustion plants (IMA) must carry out continuous self-monitoring of pollutant emissions and are required to perform parallel measurements with accredited laboratories, to certify results. Thus, INCD INSEMEX Petroșani, through the Testing Laboratories Group, accredited by RENAR, offers these type services to various economic agents. The curent paper presents measurements performed at two IMA exhaust chimneys, in two different stages, to quantify pollutants released into the atmosphere and to establish the impact they generate on health of population in the area of the study. Analysis of results showed that the maximum allowed value for the SO2 was exceeded, so that, at the end of this paper, some recommendations were reviewed, according to BAT (Best Available Techniques), to support the economic agent and inhabitants of the area in haveing a cleaner environment.
Studies on the exposure of workers to fine particles from diesel engine exhaust emissions generated in urban transport
Authors: Haiducu Maria , Ștepa Raluca-Aurora , Scarlat Iuliana-Pamela , Chiurtu Elena-Ruxandra
Published: December 2022

The paper presents the results of the studies on the exposure of workers who may face exhaust emissions of diesel engines from urban transport. Many workers such as drivers, toll booth workers, security guards, public domain workers, police officers may be exposed daily to the chemical pollutants from urban transport. It is estimated that 52% of annual occupational deaths in the European Union can be attributed to work-related cancers. The study responds to the actions to prevent the exposure of workers to carcinogens that the European Commission has included in theEurope’s Beating CancerPlan adopted in early 2021.
Analysis of total content of petroleum products in water by using FTIR spectroscopy
Authors: Simion Alexandru Florin , Găman Angelica Nicoleta , Lăutaru Vlad Alexandru
Published: December 2022

Contamination of aquatic and terrestrial environment with oil products is a major problem in processes of extraction, transport and processing of crude oil. Derived organic compounds, resulting from fractional distillation of crude oil often end up in wastewater and surface water causing irreversible effects on aquatic ecosystems. Thus, it’s necessary to identify and qualitatively determine the total content of petroleum products in water, by classical chemical, chromatographic and infrared spectroscopy methods. Gathering high-resolution spectral data was performed by a modern method, Fourier transform infrared spectrometry (FTIR), a relatively precise, high accuracy data method. The study’s main purpose is to describe most important steps to be followed to obtain representative results for the use of FTIR spectrometry in determining total content of petroleum products in water. Steps described in the study involve drawing the baseline, calibrating the method with certified reference materials and estimating the uncertainty degree of the analysis method used. The study of total content of petroleum products is addressed especially to researchers in the field of analytical chemistry to update the methods used, environmental engineers to estimate the pollution degree of a body of water and (PhD) students who want to deepen the field of petroleum compounds analysis.
Car access to mountain resorts - advantages and disadvantages. Case study: Parâng Resort
Authors: Apostu Izabela-Maria , Faur Florin
Published: December 2022

Tourism stimulates economic growth and the development of local communities. The mountain areas, as points of tourist attraction, represent real treasures in terms of the spectacular landscapes, the specific geological and floristic elements and the diversity of sports and activities that can be practiced. Problems such as long distance from areas of interest (localities), difficult access, harsh climatic conditions, vulnerability to natural disasters prevent the development of mountain resorts and mountain tourism. Access to mountain resorts is one of the most discussed issues. While some are making sacrifices to find sustainable solutions to give tourists access to the resorts, others apply simpler solutions, such as building roads and allowing public traffic. The existence of modernized access roads supports the development of a mountain resort in the sense that tourists can get comfortably, safely and as close as possible to the existing objectives using their personal car, without depending on other means of transport. However, this comfort is accompanied by a number of advantages and disadvantages, which are analyzed in this paper and highlighted by the case study method. For this purpose, the county road DJ709F, recently modernized, which provides car access to Parâng Resort, located in Parâng Mountains, was studied.
Presenting air quality status through hot spot maps realized by using Kernel Density Estimation (KDE) - case study: Craiova, 2020/2021
Authors: Moldovan Clementina , Sbirna Sebastian , Sbirna Liana-Simona
Published: December 2022

As hot spot mapping has become an usual technique used worldwide in order to obtain a clearer view on the geographic incidence of several factors from the most diverse fields, this paper aims to present a case study (developed late 2020 and early 2021) regarding air quality status of Craiova – an important Romanian city – involving the most relevant three gaseous air pollutants. The study has been realized by using a modern technique for generating hot spot maps on grids, as smooth continuous surfaces, which is Kernel Density Estimation (KDE).
The role of university - business partnerships in increasing students entrepreneurial skills
Authors: Isac Claudia , Niță Dorina , Nimară Ciprian
Published: December 2022

In this paper, we first bone up on the literature as regards the relationship between universities and the business environment and its role on the development of entrepreneurship as an engine of economic growth. We continued the paper by presenting this relationship in the context of introducing projects related to entrepreneurship within the University of Petroșani. In the methodology part, on the one side, the university - business entity partnerships are statistically analyzed and on the other side, the results of a enquiry that was applied to entrepreneurs during 2019-2021 within the POCU project ”EU - ENTREPRENEUR - increase of students participation from vulnerable categories to undergraduate study programs through entrepreneurial innovation ”POCU Contract /379/6/21. The paper brings to interesting conclusions about the relationship between universities and entrepreneurs and how it can intensify the efficiency of this collaboration from the perspective of increasing the entrepreneurial skills of students.
On industrial tourism as a viable perspective for the Jiu Valley
Authors: Samuil Ionela , Ionică Andreea-Cristina
Published: December 2022

The need to recognize the value of technological structures as elements of heritage has led to the establishment and development of industrial tourism. The interest in the conservation of abandoned industrial sites has not only scientific but also economic and heritage importance, especially for the regions severely affected by the industrial restructuring process. This process has had disastrous consequences, especially for the mono-industrial regions dominated by a single field of activity. One such example is the Jiu Valley, which was one of the most industrialized areas of the country and the main cities based their economy on the mining industry. But the Jiu Valley is defined not only by mining and mines, by cities and people with a precarious financial situation but also by hospitable cities and people, eager to share their traditions and culture. In this context, the article identifies the potential of exploitation of industrial structures in tourism, thus supporting the perspective component of revitalization by reuse of a mining perimeter. Investments in cultural heritage can lead to positive effects for the local economy not only in terms of cultural consumption, but also in terms of increasing the number of jobs and incomes.
J. curcas and Manihot esculenta are potential super plants for phytoremediation in multi-contaminated mine spoils
Authors: Mensah Martin Kofi , Drebenstedt Carsten , Uchenna Okoroafor Precious , Wiafe Edward Debrah
Published: December 2022

Phytoremediation approaches have increasingly been applied in environmental remediation projects. In this study, the potentials of Manihot esculenta (M. esculenta), Vigna unguiculata (V. unguiculata) and J. curcas curcas (J. curcas) in remediating multi-contaminated mine spoils was evaluated. The target potentially toxic elements (PTEs) are Cd, As, Zn, Pb, and Hg. The test plants were grown and monitored under growth stress conditions for 270 days. Using inductively Coupled Plasma- Mass Spectrometry and EPA method 200.8, the total elemental contents in the shoot and root parts of the plants were determined. Significant differences (p< 0.01) were observed in the uptake performance of the test plants. For example, M. esculenta and J. curcas, bioaccumulated 50- 80 % of the various baseline PTE contents in their root parts at 270 days after planting. In contrast, < 27 % of PTEs were found in the root parts of V. unguiculata, except Zn at 70 %. Growth stressors and soil PTEs were factors that reduced biomass production in respective plants by 25 %. Cummulatively, the performance order M. esculenta> J. curcas> V. unguiculata was observed for multi-contaminant removal in soils. Techniques for enhancing the easy cultivation of the test plants are recommended to enhance their applicabilities in phytoremediation projects.
Beyond the Lungs—Emerging Challenges in Adult Cystic Fibrosis Care
Authors: Mulrennan Siobhain , Sapru Karuna , Tewkesbury Daniel , Jones Andrew M.
Published: December 2022

Cystic fibrosis (CF) is a multisystem disease. This article provides an up-to-date review of many of the nonrespiratory complications of CF, including mental health issues, nutritional and gastrointestinal problems, fertility issues, diabetes mellitus, bone health and musculoskeletal problems, liver disease, renal problems, and risk of malignancy. It highlights the recent impact of new therapies, including CF transmembrane conductance regulator modulators, on the nonrespiratory complications of CF and provides insights into the potential challenges faced by an aging population of adults with CF and their caregivers, including the potential future risk for cardiovascular disease.
Interventional Radiology Procedures of the Shoulder
Authors: Fawcett Richard , Rowbotham Emma
Published: December 2022

Using imaging guidance to perform procedures around the shoulder girdle has become established practice in musculoskeletal radiology. Whether it be therapeutic injections for intra-articular pathology, rotator cuff or subacromial/subdeltoid bursal pathology, or injections for diagnostic purposes, such as magnetic resonance or computed tomography arthrography, a range of techniques and imaging modalities can be used. This article discusses the techniques for commonly performed procedures.
A qualitative study of pre-service teachers’ experienced benefits and concerns of using motivational interaction in practice after a training course
Authors: Renko Elina , Koski-Jännes Anja , Absetz Pilvikki , Lintunen Taru , Hankonen Nelli
Published: December 2022

Despite its positive effects on physical activity promotion, the motivational style of interaction by health professionals is not easily taken up, as shown by meta-analyses of training courses. The concerns professionals experience for taking up novel skills remain an open question. Preservice physical education teachers were offered a 16-h training course on motivational interaction, an approach to teacher–student interaction based on the synthesis of self-determination theory and motivational interviewing. This study investigates what benefits and concerns pre-service PE teachers experience when trying to adopt this new style of interaction and use its specific techniques. Individual interviews (N = 19) of pre-service PE teachers were conducted after the training course. The narrative approach was first used to analyse participants’ experiences of using motivational interaction. Two types of storylines emerged, one enthusiastic and optimistic and the other one partly reluctant. Concerns and benefits of using specific techniques were then selected as suitable units of analysis and inductive content analysis was employed to further analyse the units. The analysis process included open coding, creating categories, and abstraction. Participants described positive professional transformation through learning motivational interaction. Expressed benefits included reducing conflicts and developing good relationships. Participants also voiced concerns that were grouped under four categories: (1) problems in delivering the techniques in group situations, (2) mismatch with professional role demands, (3) undesired effects on personal interaction, and (4) target behaviour (technique-) related concerns. These overarching categories covered a variety of concerns, e.g., losing control of situations, and the challenge of allocating time and feedback equally among students. To successfully uptake style and techniques of motivational interaction, pre-service teachers may have to re-evaluate their role and the power relations within the target group. Utilizing the Theoretical Framework of Acceptability, we discuss how interaction training can address experienced concerns in order to improve the delivery, effectiveness, and acceptability of such training programs.
Complex nonlinear dynamics of polarization and transverse modes in a broad-area VCSEL
Authors: Bittner Stefan , Sciamanna Marc
Published: December 2022

Lasers can exhibit nonlinear and chaotic dynamics driven by the interaction of multiple lasing modes, and investigating the different scenarios of mode competition and bifurcations of their dynamics is of great interest on a fundamental level as well as in view of applications. We study the dynamics of a broad-area vertical-cavity surface-emitting laser (VCSEL) in solitary continuous-wave operation with a comprehensive investigation of its polarization state, lasing spectra, near-field distributions, and temporal dynamics. Fluctuations at the frequency of birefringence splitting and other frequency components develop in a series of bifurcations. The bifurcations coincide with changes of the transverse lasing modes and/or the polarization state, demonstrating the importance of both the spatial and polarization degrees of freedom for mode competition. As a consequence, the inherent nonlinear dynamics of broad-area VCSELs is significantly more complex than the dynamics of VCSELs with a single spatial mode.
Beliefs about minority representation in policing and support for diversification
Authors: Peyton Kyle , Weiss Chagai M. , Vaughn Paige E.
Published: December 2022

Diversification of police forces is widely promoted as a reform for reducing racial disparities in police–civilian interactions and increasing police legitimacy. Despite these potential benefits, nearly every municipal police department in the United States remains predominately White and male. Here, we investigate whether the scale and persistence of minority underrepresentation in policing might partly be explained by a lack of support for diversification among voters and current police officers. Across two studies (
N
 = 2, 661) sampling the US adult population and residents from a city with one of the least representative police forces in the country, individuals significantly overestimate officer diversity at both the local and national levels. We find that correcting these biased beliefs with accurate information reduces trust in police and increases support for hiring new officers from underrepresented groups. In the municipal sample, these corrections also cause an increase in residents’ willingness to vote for reforms to diversify their majority White police department. Additional paired decision-making experiments (
N
 = 1, 663) conducted on these residents and current police officers demonstrate that both prefer hiring new officers from currently underrepresented groups, independent of civil service exam performance and other hiring criteria. Overall, these results suggest that attitudes among voters and police officers are unlikely to pose a major barrier to diversity reforms.
Ancient inhabitants of the Basin of Mexico kept an accurate agricultural calendar using sunrise observatories and mountain alignments
Authors: Ezcurra Exequiel , Ezcurra Paula , Meissner Ben
Published: December 2022

In the hot dry spring of monsoon-driven environments, keeping an accurate calendar to regulate the annual planting of crops is of critical importance. Before the Spanish conquest, the Basin of Mexico had a highly productive farming system able to feed its very large population. However, how they managed to keep their farming dates in synchrony with the solar year is not known. In this paper, we show that the observation of sunrise against the Basin’s eastern horizon could have provided an accurate solar calendar and that some important sunrise landmarks coincide well with the themes of seasonal festivities described in early codices. We also show that a long stone causeway in the summit of Mount Tlaloc aligns perfectly with the rising sun on February 23 to 24, in coincidence with the Basin’s new year in the Mexica calendar. Third, we demonstrate that, when viewed from the sacred Mount Tepeyac in the bottom of the Basin, sunrise aligns with Mount Tlaloc also on February 24. The importance of Mount Tlaloc as a calendric landmark seems to be corroborated by illustrations and texts in ancient Mexica codices. Our findings demonstrate that by using carefully developed alignments with the rugged eastern horizon, the inhabitants of the Basin of Mexico were able to adjust their calendar to keep in synchrony with the solar year and successfully plan their corn harvests.
Survey of international academic centers and institutes focused on human-animal bond: Scope and landscape in 2021
Authors: Nieforth Leanne O. , Leighton Sarah C. , Miller Elise A. , O’Haire Marguerite E.
Published: December 2022

Routine surveying of academic centers focused on the human-animal bond is critical to understand the trajectory of the field and to create an environment where centers can learn from one another and build collaborations. The purpose of this manuscript was to report the findings of a survey of these human-animal bond centers, to summarize the status of the field, and to identify changes within the field since 2016. Survey questions concentrated on the demographic characteristics, engagement programs, educational opportunities, and research focuses of the centers. Findings suggest that the field continues to grow as one-third of human-animal bond centers are less than 10 years old. The number of centers that participated in this survey increased by 31% compared with the previous survey. Centers have developed a variety of engagement programs, including animal-assisted intervention and companion animal education programs. About half of the centers (48%) offer degree programs and about one quarter of the centers (24%) offer certificate programs. Most centers (95%) focus their research on companion animals with the most studied companion animal being dogs (95%). The most frequent data collection method was surveys (86%). Qualitative analyses, behavior measures, and physiological measures were also common. The most notable changes from the 2016 survey include overall growth of the field (indicated by the establishment of new centers) and a shift in the specialty area of directors, moving from 44% of directors being veterinarians in 2016 survey to 90% having a human-focused specialty in the 2021 survey. Most centers’ research focused on animal-assisted interventions that are consistent with the previous survey. As the field of the human-animal bond continues to grow and more centers emerge, ongoing evaluation of offerings is important to track changes, identify needs, and foster success.
Dry sliding wear behaviour of AZ91–Mg2Si–SiC hybrid composites at elevated temperatures
Authors: Zarghami Mohammad , Emamy Massoud , Malekan Mehdi , Mansouri Amir
Published: December 2022

The dry sliding wear behaviours of extruded AZ91–Mg2Si– xSiC composites were studied under a normal load of 20N at various temperatures of 25–250°C, using a pin-on-disc tribometer. The results showed a decrease in wear rates of samples with an increase in temperature from 100°C to 200°C by about 40–80%, due to the formation of an oxygen-rich tribo-layer on the worn surfaces. At 200°C, the wear rate of AZ91–Mg2Si–10SiC hybrid composite was 54% lower than that of AZ91–Mg2Si composite and AZ91 alloy. A mechanically mixed layer comprised of iron and magnesium oxides on the worn surface of the hybrid composite protected the surface from more wear. Oxidation and plastic deformation were dominant wear mechanisms at wear temperatures from 25°C to 200°C.
Bayesian hierarchical dictionary learning
Authors: Waniorek N , Calvetti D , Somersalo E
Published: December 2022

Dictionary learning, aiming at representing a signal in terms of the atoms of a dictionary, has gained popularity in a wide range of applications, including, but not limited to, image denoising, face recognition, remote sensing, medical imaging and feature extraction. Dictionary learning can be seen as a possible data-driven alternative to solve inverse problems by identifying the data with possible outputs that are either generated numerically using a forward model or the results of earlier observations of controlled experiments. Sparse dictionary learning is particularly interesting when the underlying signal is known to be representable in terms of a few vectors in a given basis. In this paper, we propose to use hierarchical Bayesian models for sparse dictionary learning that can capture features of the underlying signals, e.g. sparse representation and nonnegativity. The same framework can be employed to reduce the dimensionality of an annotated dictionary through feature extraction, thus reducing the computational complexity of the learning task. Computed examples where our algorithms are applied to hyperspectral imaging and classification of electrocardiogram data are also presented.
Regulating film crystallization kinetics with thiourea additive in Cs2AgBiBr6 solar cells
Authors: Zhang Lun , Xu Yinyan , Niu Pujun , Lyu Mei , Lu Hongbo , Zhu Jun
Published: December 2022

Cs2AgBiBr6 solar cells have the advantages of non-toxicity and high stability and are regarded as one of the most promising novel solar cells. The crystallization kinetics of the films play a crucial role on the film microstructure and the optoelectronic properties. Herein, thiourea is introduced into the Cs2AgBiBr6 precursor solution as an additive. Fourier transform infrared spectroscopy characterization confirms that thiourea acts as a Lewis base to form an adduct with Ag+, Bi3+. The modified Cs2AgBiBr6 film is used to fabricate solar cells. As a result, the power conversion efficiency and the open-circuit voltage of the optimized device are 1.65% and 1.07 V, significantly higher than the control device (1.04% and 0.89 V). Dark current–voltage, electrochemical impedance spectroscopy, etc, reveal that defects and recombination in the solar cells are inhibited. This work provides an effective method to regulate the crystallization kinetics of Cs2AgBiBr6 film and is helpful for further enhancement of the photovoltaic performance of Cs2AgBiBr6 solar cells.
A body-size-dependent series of Chinese adult standing phantoms for radiation dosimetry
Authors: Luo Xiyu , Qiu Rui , Wu Zhen , Yan Shuchang , Zhang Hui , Li Junli
Published: December 2022

Phantoms of different sizes, as indicated by several studies, have a significant impact on the accuracy of dose calculations. Therefore, it is necessary to establish a body-size-dependent series of Chinese standing adult phantoms to improve the accuracy of radiation dosimetry. In this study, the Chinese reference polygon-mesh phantoms

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have been refined and a method for automatically constructing lymph nodes in a mesh phantom has been proposed. Then, based on the refined phantoms, this study has developed 42 anthropometric standing adult computational phantoms, 21 models for each gender, with a height range of 145–185 cm and weight as a function of body mass index corresponding to healthy, overweight and obese. The parameters were extracted from the National Occupational Health Standards (GBZ) document of the People’s Republic of China, which covers more than 90% of the Chinese population. For a given body height and mass, phantoms are scaled in proportion to a factor reflecting the change of adipose tissue and the internal organs. The remainder is adjusted manually to match the target parameters. In addition, the constructed body-size-specific phantoms have been implemented in the in-house THUDose Monte Carlo code to calculate the dose coefficients (DCs) for external photon exposures in the antero-posterior, postero-anterior and right lateral geometries. The results showed that organ DCs varied significantly with body size at low energies (

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) and high energies (

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) due to the differences in anatomy. Organ DC differences between a phantom of a given size and a reference phantom vary by up to 40% for the same height and up to 400% for the whole phantom. The influence of body size differences on the DCs demonstrates that the body-size-dependent Chinese adult phantoms hold great promise for a wide range of applications in radiation dosimetry.
Tuning of electronic bandgap and electronic transport properties of double perovksites A2NaScI6(A = Rb, Cs) for energy device applications
Authors: Alburaih Huda A , Noor N A , Rashid M , Nazir Sadia , Laref A
Published: December 2022

Non-toxicity, ecosystem stability, and distinct performance are the reasons to make halide-based perovskites suitable for solar and thermoelectric purposes. This paper studied elastic properties and structural stability of cubic phase double perovskites (DPs) A2NaScI6 (A = Rb, Cs) by Born stability criteria and tolerance factor. Moreover, we comprehensively examine these DPs in terms of elastic, electronic, optical, and transport behavior. The bandgap range 2.80–2.70 eV is discerned in the electronic band structure and contributes to optoelectronic devices. Most of the absorption is observed in the visible region, and bandgap is reduced by interchanging Rb with Cs atom. The dielectric constants and other optical factors are used to reveal the optical properties of A2NaScI6 (A = Rb, Cs). In the last, the thermoelectric characteristics are calculated by employing BoltzTrap code. The calculated value of the figure of merit (ZT) intimates that the analyzed materials are apposite for thermoelectric purposes.
Effect of dusty plasma parameters on the low frequency Hall current instability
Authors: Sarkar Sanjib , Atul Jyoti K , Laishram Modhuchandra
Published: December 2022

The effect of power-law dust size distribution and dust number density on the low frequency hall current instabilities have been studied in and above the equatorial electrojet altitudes using a linear fluid model consisting of electrons, ions and dust particles. The dispersion relation includes electron and ion drift perpendicular to the equilibrium uniform electric and magnetic field, mass and pressure of the charged species and collision between charged and neutral particles. The effect of dust size variation and dust number density on the instability have been investigated by varying the dust-plasma frequency in the dispersion relation. It has been found that in the region of the electrojet altitudes the variation of dust size for the case of broad dust size distribution and dust number density can substantially increase the growth rate and frequency of the instability. However, above the electrojet region where ions become weakly magnetized, the above two dust parameters have a negligible effect on the instability.The present analysis is applicable to the dusty meteor trail plasma of the ionospheric E-region.
Production of spin coated chromium oxide (CrO3) thin layers and application in the Al/p-Si metal semiconductor structures
Authors: Güllü Ö , Tataroğlu A
Published: December 2022

A novel Al/CrO3/p-Si structure was built by help the spin coating technique. CrO3 thin layer has been characterized by the XRD, UV–vis, SEM and AFM measurements. It has been observed that the CrO3 layer has amorphous structure with optical band energy value of 3.96 eV. The surface analysis of CrO3 layer by using AFM and SEM methods has been found to be rather rough that is not observed grains of any definite shape or size. Furthermore, some electronic quantities of Al/CrO3/p-Si junction by help the thermionic charge transport mechanism have been extracted by utilizing current-voltage (I-V) and capacitance-voltage data. Moreover, it has been seen that interfacial state concentration for the Al/CrO3/p-Si contact varied in the range of 8.05 × 1012 eV−1 cm2 to 6.71 × 1011 eV−1 cm−2 in darkness, and 1.23 × 1013 eV−1 cm−2 to 3.82 × 1012 eV−1 cm−2 under the illumination condition. The photoelectric parameters of the Al/CrO3/p-Si contact under 100 mW cm−2 light illumination was studied by I-V measurement.
Clarifying some common misconceptions about the expansion of the universe
Authors: Re Fiorentin Stefano
Published: December 2022

Modern cosmology is based on a 6-parameter model, called Lambda-CDM, which provides an accurate description of the expansion of the Universe on the basis of measured parameters. However, there are attempts to give ‘phenomenological’ descriptions of the dynamics of the Universe that are inconsistent with this model and sometimes lead to misconceptions. They stem from a Newtonian approach that interprets the expansion as due to an ‘initial kick’ that placed all matter and energy in the Universe on ‘inertial trajectories’. These descriptions do not conform to the relativistic approach. Here we show that the Einstein field equations trace the expansion of cosmic space directly to the increase in the energy content of the observable universe caused by the additional space entering it as a consequence of the forward motion of its horizon. We derive here the connection between variations in the scale factor and the corresponding variations in the energy of the observable universe, in the case of the most general cosmological model. We then obtain explicit closed-form expressions of this relationship both in the case of the Universe of any curvature and containing matter and radiation, and in the case of the de Sitter universe, characterized by the cosmological constant only. Some interesting features are pointed out, both in terms of the energy growth rate of the observable universe in the various cosmological models, and in terms of the dynamics of the scale factor. Finally our demonstration is corroborated by an analogy between the expansion of cosmic space and the gravitational stretching of space at the center of a sphere of uniform density whose radius increases with time. This analogy, which allowed us to obtain the novel closed-form expression of the stretching of space at the centre of such a sphere, confirmed that the paradigm that ‘gravity expands space’ is valid in both systems.
Double tangent method for two-periodic Aztec diamonds
Authors: Ruelle Philippe
Published: December 2022

We use the octahedron recurrence, which generalizes the quadratic recurrence found by Kuo for standard Aztec diamonds, in order to compute boundary one-refined and two-refined partition functions for two-periodic Aztec diamonds. In a first approach, the geometric tangent method allows to derive the parametric form of the arctic curve, separating the solid and liquid phases. This is done by using the recent reformulation of the tangent method and the one-refined partition functions without extension of the domain. In a second part, we use the two-refined tangent method to rederive the arctic curve from the boundary two-refined partition functions, which we compute exactly on the lattice. The curve satisfies the known algebraic equation of degree 8, of which either tangent method gives an explicit parametrization.
Exact computation of heat capacities for active particles on a graph
Authors: Khodabandehlou Faezeh , Krekels Simon , Maes Irene
Published: December 2022

The notion of a nonequilibrium heat capacity is important for bio-energetics and for calorimetry of active materials more generally. It centers around the notion of excess heat or excess work dissipated during a quasistatic relaxation between different nonequilibrium conditions. We give exact results for active random walks moving in an energy landscape on a graph, based on calculations employing the matrix-tree and matrix-forest theorems. That graphical method applies to any Markov jump process under the physical condition of local detailed balance.
Optimization of Water & Heat Management System for Automobile PEMFCs with Fuzzy PID Control
Authors: Jing Xubao , Liu Conghao , Guo Yu , Cai Siyuan
Published: December 2022

In order to solve problems like the decline of energy efficiency of cells, or the large temperature difference in the outlet and inlet of electric piles, which are caused by unstable temperature during the operation of PEM fuel cells, the authors established models in the simulation software—Simcenter AMESim, such as the electric piles of fuel cells, automobiles, drivers, engines, and gas supply, so the performance of fuel cells could be studied. The authors also adopted a Fuzzy PID controller, which was compared to the traditional PID controller in terms of control effects under the operating conditions of the New European Driving Cycle (NEDC). The comparison and analysis results reveal that a water & heat management system adopting a Fuzzy PID controller could better adjust the temperature & humidity of cells, keep the temperature difference between the outlet and inlet of electric piles under 3°C, and raise the output voltage by 2.35%. The results of this study can, to some extent, serve as the basis for other studies on PEM fuel cells.
An objective assignment method for siting new energy plants
Authors: Piao Zheyong , Guo Dongwei , Peng Tao , Zhangyang Siqi , Li Xue , Liu Hao
Published: December 2022

This paper proposes a multi-criteria decision-making method for new energy power station site selection based on a fuzzy comprehensive analysis method. It is applied to make multi-criteria analysis decisions on the target location when selecting the address for building a new energy power station, to ensure the reasonableness of the corresponding weights of each index, and to give reasonable and scientific suggestions for decision-makers to obtain the expected results. We analyze the mechanism of the sequential relationship analysis method and fuzzy inverse entropy weighting method from the perspective of the index assignment method, and combine the two assignment methods by linear weighting, so as to lay the foundation for further construction of a multi-attribute hybrid index system with the coexistence of qualitative and quantitative indexes.
Smart park electricity-carbon coupling measurement technology considering distributed energy access
Authors: Qie Wei , Li Ziming , Wang Bin , Li Da
Published: December 2022

With the increasing energy consumption of buildings, how to cooperate and share buildings with a high proportion of distributed energy access has important research significance. Taking the buildings with a high proportion of distributed energy access as the research object, this paper proposes an interactive sharing mechanism for electricity use and carbon emission rights in smart parks. Firstly, a smart park carbon metering and building cluster market trading mode considering carbon emission right surplus and gray power supply and demand is constructed. The electricity carbon metering model of purchasing electricity from the distribution network is constructed. Finally, a new method is proposed based on the improved intelligent building cluster electric carbon coupling sharing model and optimization of electric carbon. The effectiveness and superiority of the smart park electricity carbon coupling measurement technology and the optimization method proposed in this paper are proven through experimental verification.
Modeling Method for Prediction of Primary Frequency Modulation Compensation Capability
Authors: Li Yuanyuan , Liu Enren , Shi Shuo , Wang Yuqi
Published: December 2022

The primary frequency modulation function of thermal power units plays an important role in the frequency stability of the power grid. In order to accurately predict the compensation capacity of primary frequency modulation, this paper introduces a modeling method to predict the compensation ability of primary frequency modulation. In this paper, the network source information platform data is used to collect the historical information of the remote test of primary frequency modulation, and the historical data are selected for fitting according to the principle of the closest working condition of the unit, so as to predict the 1-minute compensation ability of the primary frequency modulation of a single generator set. The function has been put into operation on the network source information platform, and the prediction results are verified by the remote test results during the provincial adjustment period. It shows that the error between the prediction results and the actual results is small, and the load changes within 1 min can be expressed more accurately.
Experimental study on flow and heat transfer performance of condensing gas-fired boiler
Authors: Cao Weixue , Wei Fan , Liu Fengguo , Li Jun , Sun Bo , Zhao Lei
Published: December 2022

In the process of energy utilization, a large amount of heat transfer needs to be realized through the heat exchange process. Therefore, the development of efficient enhanced heat exchange technology has important theoretical and application value for realizing the efficient utilization of energy and reducing pollutant emissions. Condensing heat exchanger is the core component of condensing water heater. Firstly, this paper analyses the development trend of condensing heat exchanger at home and abroad, and studies the heat exchange, pollutant emission and structural optimization design of condensing heat exchanger by using the gas water heater test-bed. Using the field synergy theory, the flow channel and fin structure of the heat exchanger are optimized. The series flow channel on the water side of the heat exchanger is optimized as the structure of first parallel and then series flow, so that the heat transfer capacity of the water side of the heat exchanger can be increased by 5.6% at the maximum, the reduction of NOx emission concentration is relatively less than 6.7%.
Power and Electricity Balance Analysis Method Based on the Full Sequence Production Simulation Method
Authors: Xin Ma
Published: December 2022

The goal of “carbon peaking and carbon neutralization” has accelerated the pace of China’s energy transformation and power grid upgrading. During the 14th Five Year Plan period, the characteristics of the high proportion of new energy and multi-DC transmission in the power system have become increasingly prominent, and the ‘double peak’ load characteristics have gradually emerged. The power grid is facing the challenges of power shortage and new energy obstruction in some periods. Therefore, considering the growth of power installed capacity and load level, according to the power balance and the new energy consumption of the provincial power transmission network, the full sequence production simulation method is used to analyze the power and electricity balance of the whole network considering the energy storage device and demand side response to provide support for the provincial power transmission network planning during the 14th Five Year Plan period.
SDR-based General Simulation System for Power Internet of Things
Authors: Zhong Han , Suo Siliang , Chen Liming , Kuang Xiaoyun , Huang Kaitian
Published: December 2022

With the continuous construction and improvement of the digital power grid, the communication technology of the Power Internet of Things (PIoT) presents a trend of diversification. In order to work out the difficult problem of communication simulation tests in the PIoT, this paper proposes a simulation system based on SDR. The system not only combines the programmability of software simulation but also retains the hardware part of communication technology so that it can meet the simulation test needs of different communication technologies. Finally, according to the simulation requirements of China Southern Power Grid’s wireless communication technology, we built a simulation environment based on USRP and implemented experimental simulation examples using LoRa and MQTT. In this system, we have realized the access and support of varieties of wireless communication technologies and protocols, which can well meet the simulation needs of various wireless communication technologies of China Southern Power Grid.