bluuebunny/crossref_metadata_2025 huggingface dataset:
A pair of homotopy-theoretic version of TQFT’s induced by a Brown functor
Authors: Kim Minkyu
Published: June 2021

The purpose of this paper is to study some obstruction classes induced by a construction of a homotopy-theoretic version of projective TQFT (projective HTQFT for short). A projective HTQFT is given by a symmetric monoidal projective functor whose domain is the cospan category of pointed finite CW-spaces instead of a cobordism category. We construct a pair of projective HTQFT’s starting from a [Formula: see text]-valued Brown functor where [Formula: see text] is the category of bicommutative Hopf algebras over a field [Formula: see text] : the cospanical path-integral and the spanical path-integral of the Brown functor. They induce obstruction classes by an analogue of the second cohomology class associated with projective representations. In this paper, we derive some formulae of those obstruction classes. We apply the formulae to prove that the dimension reduction of the cospanical and spanical path-integrals are lifted to HTQFT’s. In another application, we reproduce the Dijkgraaf–Witten TQFT and the Turaev–Viro TQFT from an ordinary [Formula: see text]-valued homology theory.
Integrating Amdahl-like Laws and Divisible Load Theory
Authors: Cao Yang , Wu Fei , Robertazzi Thomas
Published: June 2021

A simple means of integrating the characteristics of networked processors under divisible loads into Amdahl’s Law is presented. Amdahl’s Law serves as an upper bound to these speedup results. Amdahl’s Law with divisible load processing characteristics included serves as an upper bound to speedup for any model taking into consideration more detailed peculiarities of real systems such as the overhead of task creation, synchronization, resource contention and memory issues.
Lorentz invariance of basis tensor gauge theory
Authors: Basso E. , Chung Daniel J. H.
Published: June 2021

Basis tensor gauge theory (BTGT) is a vierbein analog reformulation of ordinary gauge theories in which the vierbein field describes the Wilson line. After a brief review of the BTGT, we clarify the Lorentz group representation properties associated with the variables used for its quantization. In particular, we show that starting from an SO(1,3) representation satisfying the Lorentz-invariant U(1,3) matrix constraints, BTGT introduces a Lorentz frame choice to pick the Abelian group manifold generated by the Cartan subalgebra of U(1,3) for the convenience of quantization even though the theory is frame independent. This freedom to choose a frame can be viewed as an additional symmetry of BTGT that was not emphasized before. We then show how an [Formula: see text] permutation symmetry and a parity symmetry of frame fields natural in BTGT can be used to construct renormalizable gauge theories that introduce frame-dependent fields but remain frame independent perturbatively without any explicit reference to the usual gauge field.
Study on the mechanism of water transport near the surface of pristine and nitrogen-doped β-graphyne
Authors: Nan Haifeng , Zhu Xinghua , Chu Ke , Lu Zhibin
Published: June 2021

The transport mechanism of water molecules on the surface of single-layer [Formula: see text]-graphyne is investigated from the first-principles calculations. The result indicates that when water molecules are adsorbed in different stances, their corresponding transport paths are different. When N atoms are doped with sp carbon atoms, the transport pathway of water molecules is opposite to that of intrinsic [Formula: see text]-graphyne, which is due to the charge transfer between atom s. Consequently, this study is conducive to understand the mechanism of nanoscale water transport on the graphyne surface and provides a theoretical basis for exploring the interaction between water and graphyne.
Graphene–TiO2for scattering layer in photoanodes of dye-sensitized solar cell
Authors: Min Kao-Wei , Chao Shi-Mian , Yu Ming-Ta , Ho Chi-Ting , Chen Pin-Ru , Wu Tung-Lung
Published: June 2021

The scattering layer in the TiO2photoanode (PAs) of dye-sensitized solar cells (DSSCs) is doped with single-layer graphene (G), and DSSC is prepared by doctor blade coating method. A small amount of graphene (0.0016 wt.%) in a graphene aqueous solution (G-AS) and a G-TiO2paste was prepared to make 2–20 wt.% of G-AS in the deionized water (DIW). The UV-Vis measurement results show that the TiO2scattering layers doped with graphene effectively improve the visible light absorption intensity of DSSC PAs and increase the current density (Jsc) from 13.84 mA/cm2to 16.20 mA/cm2. The Electrochemical Impedance Spectroscopy (EIS) measurement showed that the internal structural impedance Rk [Formula: see text] decreased from 12.086 [Formula: see text] (without graphene doping) to 9.875 [Formula: see text] at 5 wt.% of the graphene doping. The photoelectric conversion efficiency (PCE) increased from 6.56% of the original un-doped graphene to the maximum PCE value of 7.57% at 5 wt.%. The results show that the best PCE is obtained when the concentration of G-AS is 5 wt.%.
Abundant breather and semi-analytical investigation: On high-frequency waves’ dynamics in the relaxation medium
Authors: Khater Mostafa M. A.
Published: June 2021

This paper investigates the high-frequency waves’ dynamical behavior in the relaxation medium through two recent analytical schemes. This study depends on the Vakhnenko–Parkes (VP) equation that has been reduced from the well-known Ostrovsky equation. The modified Khater (MKhat) and the extended simplest equation (ESE) methods are used to handle the considered model. As a result, many novel solitary wave solutions have been obtained to construct the initial and boundary conditions. These conditions allow employing the variational iteration (VI) method to study the semi-analytical solutions of the considered model. The accuracy of solutions is explained along with showing the matching between analytical and semi-analytical solutions and comparing our obtained solutions with the previous results that have been obtained in published research papers. Moreover, the high-frequency waves’ behavior relaxation medium is illustrated through some distinct sketches. The methods’ performance shows their effectiveness, direct, easy, and consequential for studying many nonlinear evolution equations.
EXPERIMENTAL INVESTIGATION AND OPTIMIZATION OF HIGH SPEED MACHINING OF TITANIUM ALLOY FOR BIOMEDICAL APPLICATION
Authors: NGUYEN DUC NAM , CHAU NGOC-LE , DAO THANH-PHONG
Published: June 2021

The Ti-6Al-4V alloy is known as materials with high hardness and good mechanical properties. However, the machining process of this material faces many difficulties due to unfavorable machining conditions. When the machining parameters are not selected in accordance with the Ti-6Al-4V alloy, the surface quality of workpieces does not meet technical requirements. Therefore, the appropriate machining parameters are needed to upgrade the surface roughness of workpieces in high-speed machining (HSM) conditions. The main cutting forces Py and Pz, and surface roughness Rz during turning of Ti-6Al-4V alloy in HSM were investigated and evaluated in this study. The response surface method (RSM) was used to conduct experiments and establish the models of Rz, Py, and Pz under various cutting conditions of feed rate ([Formula: see text]), tool nose radius ([Formula: see text]), and approach angle ([Formula: see text]). As a result, the [Formula: see text] value has the largest impact on the Pz. Moreover, the machining parameters such as [Formula: see text], [Formula: see text], and [Formula: see text] have a great influence on the Py. The magnitude of Rz is mainly affected by [Formula: see text] value. Based on the optimal parameters, the average value of the force Pz has decreased from 238[Formula: see text]N to 169[Formula: see text]N, corresponding reduction of about 29%. The value of the force Py has reduced from 184[Formula: see text]N to 118[Formula: see text]N, corresponding reduction of about 36%. In addition, the surface roughness of the workpiece has been improved significantly from Rz of 5.6[Formula: see text][Formula: see text]m to 2.7[Formula: see text][Formula: see text]m under optimal parameters condition. The surface roughness of the workpiece after processing in high speed machining was reduced of 52% compared with cutting under non-optimal parameters condition. The best surface quality and minimum cutting force could be achieved under optimal processing parameters in high speed cutting method.
On the geometric ergodicity for a generalized IFS with probabilities
Authors: Guzik Grzegorz , Kapica Rafał
Published: June 2021

Main goal of this paper is to formulate possibly simple and easy to verify criteria on existence of the unique attracting probability measure for stochastic process induced by generalized iterated function systems with probabilities (GIFSPs). To do this, we study the long-time behavior of trajectories of Markov-type operators acting on product of spaces of Borel measures on arbitrary Polish space. Precisely, we get the desired geometric rate of convergence of sequences of measures under the action of such operator to the unique distribution in the Hutchinson–Wasserstein distance. We apply the obtained results to study limiting behavior of random trajectories of GIFSPs as well as stochastic difference equations with multiple delays.
NUMERICAL APPROACH TO QUANTIFY AND CHARACTERIZE INTERFACE MECHANICAL BEHAVIOR BETWEEN THIN LAYER SUBSTRATE AND BIOLOGICAL TISSUES
Authors: SAWAN MARWA , REDA HILAL , SAAD NADINE , HAMADEH ABBASS , BIN SUN , NASSAR GEORGES
Published: June 2021

In this paper, we investigate the behavior of biological tissues (skin) coupled to a substrate (sensor) based on a numerical model taking into account the relationship between strain/stress components at the interface. Based on this study, we understand and quantify the most appropriate biomechanical factors in order to optimize sensor/biological tissue interface conditions. A micromechanical description based on a mathematical formulation has been developed to evaluate the biomechanical behavior provided by a 2D viscoelastic model of Kelvin–Voigt. The results show a spatio-temporal law of tissue motion highlighting the need for an optimized interface for reliable data transmission in the case of connected device in a dynamic movement or in the manufacturing of intelligent and reactive prosthesis device.
Adjusting Trade-Offs in Multi-Criteria Decision-Making Problems
Authors: Kheybari Siamak
Published: June 2021

In multi-criteria decision-making (MCDM) methods, allowing trade-offs between the decision criteria may result in inappropriate conclusions. Allowing trade-offs implies that the weaknesses of an alternative in some criteria may be compensated by its strengths in other criteria. While, with some problems, there are no concerns with regard to allowing a full trade-off, in other cases, such a trade-off may not follow the actual decision-making problem. This paper proposes a new approach based on defining an upper and lower expectation level for each decision-making criterion. Indeed, the proposed approach is a framework by which the requirements of a decision-maker are considered in the criteria involved in MCDM problems. That distinction generates two primary and secondary performance matrices. The primary matrix includes the values of the alternatives with respect to the individual criterion up to the upper expectation levels of the decision-maker, while the secondary matrix, which is defined by the amounts above the upper levels and below the lower levels of the decision-maker’s expectations, contains each alternative in all the criteria and, to some extent, can exceed the upper levels of the decision-maker’s expectations. The final result of each alternative is calculated by adding its outcome in the two matrices. The results of a numerical example involving cellphone selection show how controlling the trade-offs could affect the results.
The Possibility of Quantum Medicine in Cancer Research: A Review
Authors: Faramarzpour Mahsa , Ghaderinia Mohammadreza , Abadijoo Hamed , Aghababa Hossein
Published: June 2021

There is no doubt that quantum mechanics has become one of the building blocks of our physical world today. It is one of the most rapidly growing fields of science that can potentially change every aspect of our life. Quantum biology is one of the most essential parts of this era which can be considered as a game-changer in medicine especially in the field of cancer. Despite quantum biology having gained more attention during the last decades, there are still so many unanswered questions concerning cancer biology and so many unpaved roads in this regard. This review paper is an effort to answer the question of how biological phenomena such as cancer can be described through the quantum mechanical framework. In other words, is there a correlation between cancer biology and quantum mechanics, and how? This literature review paper reports on the recently published researches based on the principles of quantum physics with focus on cancer biology and metabolism.
Dynamics of a stochastic SIRS epidemic model with standard incidence under regime switching
Authors: Xu Jiang , Wang Yinong , Cao Zhongwei
Published: June 2021

The goal of this paper is to introduce and initiate a study of a stochastic SIRS epidemic model with standard incidence which is perturbed by both white and telegraph noises. We first show persistence in the mean and then establish the sufficient conditions for extinction of the disease. Moreover, in the case of persistence, we obtain sufficient conditions for the existence of positive recurrence of the solutions by means of structuring suitable stochastic Lyapunov function with regime switching. Meanwhile, the threshold between persistence in the mean and extinction of the stochastic system is also obtained. Finally, we test our theory conclusion by simulations.
New Regionalism Reshaping the Future of Globalization
Authors: Wang Yuzhu
Published: June 2021

The new regionalism distinguishes itself from the old one that it has emerged from, amid new circumstances and is catalyzed by new impetus. Its appearance shows that the free-market economy is being challenged and that the market mechanism of resource allocation has again been taken over by political game. The United States and some major Western powers are attempting to secure their hegemony by minimizing spillover of critical technology and industry within controllable regions which would accelerate technological growth by creating effective market space. The battle over technology and industry is becoming the mainstream paradigm of major-country competition, which is being intensified by nation states’ concern over industrial security, techno-nationalism, and major-power politics — three main drivers of the new regionalism. While supporting globalization unswervingly, China has inevitably been affected by this widespread protectionism and is also embarking on the path of regional development. New regionalism could also provide another perspective to investigate the post-pandemic role of the Belt and Road Initiative and “dual circulation” strategy of China in order to consider the prospects of globalization.
The Ecosystem of Detection and Blocklisting of Domain Generation
Authors: Metcalf Leigh , Spring Jonathan M.
Published: June 2021

Malware authors use domain generation algorithms to establish more reliable communication methods that can avoid reactive defender blocklisting techniques. Network defense has sought to supplement blocklists with methods for detecting machine-generated domains. We present a repeatable evaluation and comparison of the available open source detection methods. We designed our evaluation with multiple interrelated aspects, to improve both interpretability and realism. In addition to evaluating detection methods, we assess the impact of the domain generation ecosystem on prior results about the nature of blocklists and how they are maintained. The results of the evaluation of open source detection methods finds all methods are inadequate for practical use. The results of the blocklist impact study finds that generated domains decrease the overlap among blocklists; however, while the effect is large in relative terms, the baseline is so small that the core conclusions of the prior work are sustained. Namely, that blocklist construction is very targeted, context-specific, and as a result blocklists do no overlap much. We recommend that Domain Generation Algorithm detection should also be similarly narrowly targeted to specific algorithms and specific malware families, rather than attempting to create general-purpose detection for machine-generated domains.
Treadmill Assisted Gait Spoofing (TAGS)
Authors: Kumar Rajesh , Isik Can , Phoha Vir V.
Published: June 2021

In this work, we examine the impact of Treadmill Assisted Gait Spoofing on Wearable Sensor-based Gait Authentication (WSGait). We consider more realistic implementation and deployment scenarios than the previous study, which focused only on the accelerometer sensor and a fixed set of features. Specifically, we consider the situations in which the implementation of WSGait could be using one or more sensors embedded into modern smartphones. In addition, it could be using different sets of features or different classification algorithms, or both. Despite the use of a variety of sensors, feature sets (ranked by mutual information), and six different classification algorithms, Treadmill Assisted Gait Spoofing was able to increase the average false accept rate from 4% to 26%. Such a considerable increase in the average false accept rate, especially under the stringent implementation and deployment scenarios considered in this study, calls for a further investigation into the design of evaluations of WSGait before its deployment for public use.
PRISM
Authors: Omar Hamza , Khan Omer
Published: June 2021

Multicores increasingly deploy safety-critical parallel applications that demand resiliency against soft-errors to satisfy the safety standards. However, protection against these errors is challenging due to complex communication and data access protocols that aggressively share on-chip hardware resources. Research has explored various temporal and spatial redundancy-based resiliency schemes that provide multicores with high soft-error coverage. However, redundant execution incurs performance overheads due to interference effects induced by aggressive resource sharing. Moreover, these schemes require intrusive hardware modifications and fall short in providing efficient system availability guarantees. This article proposes PRISM, a resilient multicore architecture that incorporates strong hardware isolation to form redundant clusters of cores, ensuring a non-interference-based redundant execution environment. A soft error in one cluster does not effect the execution of the other cluster, resulting in high system availability. Implementing strong isolation for shared hardware resources, such as queues, caches, and networks requires logic for partitioning. However, it is less intrusive as complex hardware modifications to protocols, such as hardware cache coherence, are avoided. The PRISM approach is prototyped on a real Tilera Tile-Gx72 processor that enables primitives to implement the proposed cluster-level hardware resource isolation. The evaluation shows performance benefits from avoiding destructive hardware interference effects with redundant execution, while delivering superior system availability.
Understanding Cache Compression
Authors: Carvalho Daniel Rodrigues , Seznec André
Published: June 2021

Hardware cache compression derives from software-compression research; yet, its implementation is not a straightforward translation, since it must abide by multiple restrictions to comply with area, power, and latency constraints. This study sheds light on the challenges of adopting compression in cache design—from the shrinking of the data until its physical placement. The goal of this article is not to summarize proposals but to put in evidence the solutions they employ to handle those challenges. An in-depth description of the main characteristics of multiple methods is provided, as well as criteria that can be used as a basis for the assessment of such schemes. It is expected that this article will ease the understanding of decisions to be taken for the design of compressed systems and provide directions for future work.
VSumVis: Interactive Visual Understanding and Diagnosis of Video Summarization Model
Authors: Sun Guodao , Wu Hao , Zhu Lin , Xu Chaoqing , Liang Haoran , Xu Binwei , Liang Ronghua
Published: June 2021

With the rapid development of mobile Internet, the popularity of video capture devices has brought a surge in multimedia video resources. Utilizing machine learning methods combined with well-designed features, we could automatically obtain video summarization to relax video resource consumption and retrieval issues. However, there always exists a gap between the summarization obtained by the model and the ones annotated by users. How to help users understand the difference, provide insights in improving the model, and enhance the trust in the model remains challenging in the current study. To address these challenges, we propose VSumVis under a user-centered design methodology, a visual analysis system with multi-feature examination and multi-level exploration, which could help users explore and analyze video content, as well as the intrinsic relationship that existed in our video summarization model. The system contains multiple coordinated views, i.e., video view, projection view, detail view, and sequential frames view. A multi-level analysis process to integrate video events and frames are presented with clusters and nodes visualization in our system. Temporal patterns concerning the difference between the manual annotation score and the saliency score produced by our model are further investigated and distinguished with sequential frames view. Moreover, we propose a set of rich user interactions that enable an in-depth, multi-faceted analysis of the features in our video summarization model. We conduct case studies and interviews with domain experts to provide anecdotal evidence about the effectiveness of our approach. Quantitative feedback from a user study confirms the usefulness of our visual system for exploring the video summarization model.
The Goldilocks Principle: A Unifying Perspective on Biochemical Adaptation to Abiotic Stressors in the Sea
Authors: Somero George N.
Published: June 2021

The ability of marine organisms to thrive over wide ranges of environmental stressors that perturb structures of proteins, nucleic acids, and lipids illustrates the effectiveness of adaptation at the biochemical level. A critical role of these adaptations is to achieve a proper balance between structural rigidity, which is necessary for maintaining three-dimensional conformation, and flexibility, which is required to allow changes in conformation during function. The Goldilocks principle refers to this balancing act, wherein structural stability and functional properties are poised at values that are just right for the environment the organism faces. Achieving this balance involves changes in macromolecular sequence and adaptive change in the composition of the aqueous or lipid milieu in which macromolecules function. This article traces the development of the field of biochemical adaptation throughout my career and shows how comparative studies of marine animals from diverse habitats have shed light on fundamental properties of life common to all organisms.
Investigating Parasitic Reactions in Anode-Free Li Metal Cells with Isothermal Microcalorimetry
Authors: Logan E. R. , Louli A. J. , Genovese Matthew , Trussler Simon , Dahn J. R.
Published: June 2021

Anode-free Li metal cells are one of the most appealing energy storage technologies beyond Li-ion batteries due to their superior theoretical specific and volumetric energy densities. However, long cycle life in an anode-free cell remains elusive due to difficulties reversibly plating and stripping metallic lithium. Isothermal microcalorimetry was used to study parasitic reactions in anode-free Li metal cells for electrolytes containing different Li salts. A new cycling protocol was used to measure the parasitic heat flow both on freshly plated Li surfaces and anode surfaces after stripping lithium. Existing methods were used to measure parasitic reactions occurring at high voltage. In both low- and high-voltage measurements, electrolytes containing LiDFOB had the highest parasitic heat flow compared to an electrolyte with LiPF6 salt. In contrast to previous studies of parasitic reactions in Li-ion batteries using isothermal microcalorimetry, the LiDFOB-containing electrolytes gave the longest lifetime despite having higher parasitic heat flow. This observation was attributed to decomposition of the LiDFOB salt, and subsequent formation of a favorable SEI layer that greatly improves plating and stripping efficiency. In-situ detection of parasitic heat flow with isothermal microcalorimetry techniques will be valuable for future studies of electrolyte design in anode-free Li metal cells.
Classification of Tennis Video Types Based on Machine Learning Technology
Authors: Gong Xun , Wang Fucheng
Published: June 2021

With the rapid development of online video data, how to find the required information has become an urgent problem to be solved. This article focuses on sports videos and studies video classification and content‐based retrieval techniques. Its purpose is to establish a mark and index of video content and to promote user acquisition through computer processing, analysis, and understanding of video content. Video tennis classification has high research and application value. This article focuses on video tennis based on the selection of the basic frame of each shot and proposes an algorithm for classification of shots based on average grouping. Based on this, we use a color‐coded spatial detection method to detect the type of tennis match. Then, it integrates the results of audiovisual analysis to identify and classify exciting events in tennis matches. According to statistics, although the number of people participating in tennis cannot enter the top ten, the number of spectators ranks fourth. Four tennis tournaments, masters, and crown tournaments are held every year around the world. Watching large‐scale international tennis matches has become a pillar of leisure and vacation for many people. Tennis matches last from two hours to four hours or more, and there are countless large and small tennis matches around the world every year, so the number of tennis records created is staggering. And artificial intelligence technology is rarely used in tennis in the sports world (5%), but football has reached 50%. Therefore, when dealing with such a large amount of data, we urgently need to find a fast and effective video retrieval classification method to find the required information. The experiment of tennis video classification research based on machine learning technology proves that the accuracy of tennis video classification reaches 98%, so this system has high feasibility.
Application on Online Process Learning Evaluation Based on Optimal Discrete Hopfield Neural Network and Entropy Weight TOPSIS Method
Authors: Hu Chuanshuang , Ma Yongmei , Chen Ting
Published: June 2021

Sustainable development education respects differences and encourages different assessment methods to evaluate students. During the epidemic, many colleges’ examinations changed from offline to online. How to fully consider students’ process learning status and make a reasonable evaluation of students is worthy of research. Based on the process learning data of a course in a university in China, this study establishes a discrete Hopfield neural network model to classify the test samples. In the process of modelling, the grey correlation analysis method is used to optimize the elements affecting students’ comprehensive evaluation index, and it solves the problem of failure of the model due to the large gap between the factors in the traditional discrete Hopfield neural network model. Then, the entropy right TOPSIS method is used to rank samples with the same evaluation grade. Teachers can objectively evaluate each student’s process learning performance according to the ranking results. Finally, the article compares and analyzes the evaluation results of various different methods. The analysis results believe that the optimized discrete Hopfield neural network is feasible in the process learning evaluation, and the model evaluation results are more objective and comprehensive.
Aerobic Exercise‐Assisted Cardiac Regeneration by Inhibiting Tryptase Release in Mast Cells after Myocardial Infarction
Authors: Bayat Mohammad , Chien Sufan , Chehelcheraghi Farzaneh
Published: June 2021

Background. Cardiovascular disease (CVD) contributes critically to the mortality, morbidity, and economic problem of illness globally. Exercise is a share of everyone’s life. Some evidence‐based studies have frequently shown a progressive correlation between physical activity and good health. Objective. The effects of daily exercise on cardiomyocyte size, collagen content (fibrosis), and releasing mast cells (MCsʼ) tryptase of the model of myocardial infarction (MI) were assessed. Methods. 40 rats were coincidentally spread into sham+inertia (control), sham+exercise, infarction+inertia, and infarction+exercise groups. An experimental model of acute MI was induced in infarction groups. One week after surgery, exercising groups were allowed to an aerobic exercise program for six weeks. At the endpoint of the study, all examinations were performed. Results. We found lesser fibrosis in sham+exercise and infarction+exercise groups compared to sham+inertia and infarction+inertia groups, respectively (p = 0.023, p = 0.001). Also, infarction groups were significantly lower than sham groups (p < 0.05) and the infarction+exercise group was significantly lower than the infarction+inertia group (p < 0.05). The effect of exercise on MCs while increased MC density and degranulation occur at the site of fibrosis, we demonstrated that exercise decreases both total MC density and degranulation in both sham and infarction groups (p < 0.05). Immunohistochemistry examinations were significantly higher expression of MCsʼ tryptase in infarction groups than sham groups (p < 0.05, p < 0.0001). Conclusion. Exercise improves fibrosis and cardiac function in both healthy and MI rats by inhibiting released MCsʼ tryptase.
A New Aerodynamic Optimization Method with the Consideration of Dynamic Stability
Authors: Baigang Mi , Xiangyu Wang
Published: June 2021

Dynamic stability is significantly important for flying quality evaluation and control system design of the advanced aircraft, and it should be considered in the initial aerodynamic design process. However, most of the conventional aerodynamic optimizations only focus on static performances and the dynamic motion has never been included. In this study, a new optimization method considering both dynamic stability and general lift-to-drag ratio performance has been developed. First, the longitudinal combined dynamic derivative based on the small amplitude oscillation method is calculated. Then, combined with the PSO (particle swarm optimization) algorithm, a dynamic stability derivative that must not be decreased is added to the constraints of optimization and the lift-drag ratio is chosen as the optimization objective. Finally, a new aerodynamic optimization method can be built. We take NACA0012 as an example to validate this method. The results show that the dynamic derivative calculation method is effective and conventional optimization design can significantly improve the lift-drag ratio. However, the dynamic stability is enormously changed at the same time. By contrast, the new optimization method can improve the lift-drag performance while maintaining the dynamic stability.
Time-Resolved Characterization of Indoor Air Quality due to Human Activity and Likely Outdoor Sources during Early Evening Secondary School Wrestling Matches
Authors: Shendell Derek G. , Gonzalez Lauren N. , Panchella Joseph A. , Morrell Jason
Published: June 2021

Despite positive health outcomes associated with physical activity as well as individual and team sports, poor indoor air and environmental quality can adversely affect human health, performance, and comfort. We conducted a 14-month field case study incorporating two winter sports regular seasons (12/2017–2/2019) including analyses of particulate matter (PMx) in air and in dust, carbon dioxide (CO2), temperature, and relative humidity (RH%) during secondary or high school wrestling activities in southern New Jersey, USA. After planning and piloting methods during the first winter sports regular season (12/2017–2/2018), during the second winter sports regular season (1–2/2019), we conducted a purposeful simultaneous real-time sampling midgymnasium adjacent to the wrestling mats. Gymnasium occupancy ranged 100–500 people. Data collected included inhalable PM10 resuspended from floor mats, fine respirable PM2.5, and indoor CO2, temperature, and RH%. Short-term real-time elevated PM10 levels were directly compared with simultaneously documented wrestling match bouts, e.g., student-athlete takedowns and pins. PM10 and PM2.5 levels were compared with other known documented activities indoors (e.g., snack bar) and sources outdoors (e.g., adjacent parking lot and major freeway). To understand CO2, temperature, and RH% data, we characterized the HS gym mechanical ventilation system—no doors or windows outdoors—and recorded occupancy during match hours. Indoor CO2 levels ranged ∼700–1000 ppm during match #1 on 1/23/2019 but ranged from ∼900 to 1900 ppm during match #2 on 1/30/2019, with >1000 ppm for the majority of the time (and throughout the entire varsity match when occupancy was at maximum). Future research should further characterize PM10 constituents in mat dust and indoor air with larger samples of schools and matches.
Assessment of Risk Factors of Noncommunicable Diseases among Semiurban Population of Kavre District, Nepal
Authors: Timalsina Punjita , Singh Regina
Published: June 2021

Noncommunicable diseases (NCDs) are posing a great threat to mankind. Timely identification, prevention, and control of common risk factors help to reduce the burden of death from NCDs. These risk factors are also closely related to lifestyle changes. This study aimed to assess the prevalence of risk factors of NCDs among semiurban population of Kavre district. Community-based cross-sectional study design using the multistage sampling method was used to select 456 respondents. Data were collected using WHO’s STEPS instruments 1 and 2. Four behavioural risk factors, i.e., current tobacco use, harmful alcohol use, physical inactivity, and inadequate servings of fruits and vegetables and two metabolic risk factors, i.e., abdominal obesity and hypertension were included in the study. The study revealed that more than one-third (36.0%; 43.0–52.2%) were current tobacco users, nearly one-sixth (15.8%; 12.7–19.4%) consumed alcohol harmfully, most of all did not have adequate servings of fruits and vegetables (95.8%; 93.6–97.3%), nearly two-thirds have abdominal obesity (62.1%; 57.5–66.4%), and more than one-fifth of population had hypertension (22.1%; 18.6–26.2%). Only 1.1% respondents were free from risk factors, while 78.5%, 46.1%, 14.5%, and 1.8% had two, three, four, and five risk factors, respectively. The co-occurrence of three or more risk factors was associated with increasing age (AOR ranging 4.7–10.9), male sex (AOR = 3.9 (2.4–6.3);

p
<
0.001

), and illiterate respondents (AOR = 1.7 (1.0–2.9);

p
=
0.038

). The study concludes that almost all adults residing in semiurban areas of Kavre district have at least one or more risk factors, and nearly half of them have three or more risk factors. This suggests appropriate preventive approaches to be focused on younger age groups, male sex, and illiterate population to reduce the prevalence of NCDs in the near future.
A Nomogram Prediction of Length of Hospital Stay in Patients with COVID-19 Pneumonia: A Retrospective Cohort Study
Authors: Li Kang , Zhang Chi , Qin Ling , Zang Chaoran , Li Ang , Sun Jianping , Zhao Yan , Feng Yingmei , Zhang Yonghong
Published: June 2021

Assessing the length of hospital stay (LOS) in patients with coronavirus disease 2019 (COVID-19) pneumonia is helpful in optimizing the use efficiency of hospital beds and medical resources and relieving medical resource shortages. This retrospective cohort study of 97 patients was conducted at Beijing You’An Hospital between January 21, 2020, and March 21, 2020. A multivariate Cox proportional hazards regression based on the smallest Akaike information criterion value was used to select demographic and clinical variables to construct a nomogram. Discrimination, area under the receiver operating characteristic curve (AUC), calibration, and Kaplan–Meier curves with the log-rank test were used to assess the nomogram model. The median LOS was 13 days (interquartile range [IQR]: 10–18). Age, alanine aminotransferase, pneumonia, platelet count, and PF ratio (PaO2/FiO2) were included in the final model. The C-index of the nomogram was 0.76 (

95
%
confidence
 
interval
 

CI

=
0.69
–
0.83

), and the AUC was 0.88 (

95
%
CI
=
0.82
–
0.95

). The adjusted C-index was 0.75 (

95
%
CI
=
0.67
–
0.82

) and adjusted AUC 0.86 (

95
%
CI
=
0.73
–
0.95

), both after 1000 bootstrap cross internal validations. A Brier score of 0.11 (

95
%
CI
=
0.07
–
0.15

) and adjusted Brier score of 0.130 (

95
%
CI
=
0.07
–
0.20

) for the calibration curve showed good agreement. The AUC values for the nomogram at LOS of 10, 20, and 30 days were 0.79 (

95
%
CI
=
0.69
–
0.89

), 0.89 (

95
%
CI
=
0.83
–
0.96

), and 0.96 (

95
%
CI
=
0.92
–
1.00

), respectively, and the high fit score of the nomogram model indicated a high probability of hospital stay. These results confirmed that the nomogram model accurately predicted the LOS of patients with COVID-19. We developed and validated a nomogram that incorporated five independent predictors of LOS. If validated in a future large cohort study, the model may help to optimize discharge strategies and, thus, shorten LOS in patients with COVID-19.
Displacement Monitoring during the Excavation and Support of Deep Foundation Pit in Complex Environment
Authors: Li Zhouqiang
Published: June 2021

Taking a super large deep foundation pit project as an example, the horizontal displacement of crown beam and driveway, surface settlement, axial force of anchor cable, and underground water level in the construction process of the foundation pit are dynamically monitored and analyzed. The excavation deformation rule of the deep foundation pit and the influence of excavation on surrounding buildings are analyzed. The results show that, with the excavation of the foundation pit, the crown beam and driveway of the foundation pit incline towards the direction of the pit and eventually tend to be stable. The variation of axial force of the prestressed anchor cable in the first layer of the foundation pit is basically consistent with the variation of horizontal displacement time history. The variation trend of the groundwater level at each side of the foundation pit is different but tends to be stable in a short time. In the whole monitoring period, the cumulative settlement value of each area of the foundation pit is within the controllable range, but the surface settlement of the north side of the foundation pit and a surrounding building has not reached stability, so it is suggested to extend the monitoring time of settlement in the relevant area.
Towards Circular Economy through Waste to Biomass Energy in Madagascar
Authors: Qin Ling , Wang Mengjun , Zhu Jinfu , Wei Yuhu , Zhou Xintao , He Zheng
Published: June 2021

Biomass energy, contributing to about 80% of the total energy supply, is considered an important energy source in Madagascar. Although around 80% of energy use comes from biomass energy, the current application method of biomass in Madagascar is still in the earliest stage, which is not safe and sustainable. This is because the main form of biomass energy used in Madagascar is still solid charcoal and wood, and the technology is limited. Thus, it is necessary to search for better ways to utilize biomass energy in Madagascar because of high prices of traditional energy carriers and massive environmental pollution. This paper reviews the following: (1) a variety of available biomass wastes for energy in Madagascar including farming residuals, animal wastes, and forest wastes, as well as urban and industrial organic wastes; (2) advanced technologies, such as gasification, torrefaction, and fermentation, that can convert these wastes to biomass energy in forms with higher energy efficiency such as biogas, biocoal briquette, and ethanol fuel, which can not only help to achieve resource utilization of wastes and circular economy but also ease the energy crisis faced by Madagascar; and (3) Madagascar focused on the development of biomass energy with strategic policies and programs. International assistance also contributes to future promotion of biomass energy. It identifies several areas where research is urgently required to adopt instrumental policies to ensure that both rural development objectives and renewable energy targets are met with financial support from the government and international assistance.
Fatigue Performance of Steel‐Concrete Composite Continuous Box Girder Bridge Deck
Authors: Zheng Yuanxun , Cao Zhanlin , Guo Pan , Gao Pu , Zhang Peng
Published: June 2021

The fatigue performance of the bridge deck significantly affects the safety and durability of the overall steel‐concrete composite beam bridge. Based on the vehicle flow information of the highway within 10 years, the fatigue performance of a two‐way four‐lane steel‐concrete composite continuous beam bridge deck is studied in this research. The results indicate that the effect of the wheel track position is negligible for two‐way four‐lane bridge when the wheel track sways laterally, and the fatigue stress of bridge deck concrete is the most unfavorable while the loading position is 7.0 m away from the bridge center line. The fatigue damage decreases by 30%–40% when the centerline of the lane deviates from the most unfavorable stress position by 1 m. The punching fatigue of the concrete is more sensitive to the changes in slab thickness, and the thickness of the deck concrete slab is recommended to be ≥35 cm.
Evaluation of Favorable Shale Gas Intervals in Dawuba Formation of Ziyun Area, South Qian Depression
Authors: Yuan Kun , Huang Wenhui , Fang Xinxin , Wang Ting , Lin Tuo , Chen Rong
Published: June 2021

A series of qualitative descriptions and quantitative analyses was used to determine the lithofacies characteristics and recognize the favorable shale intervals of Dawuba Formation in the Ziyun area of South Qian Depression. The qualitative descriptions include core description and scanning electron microscope (SEM) observation. The quantitative analyses include X-ray diffraction, total organic content analysis, vitrinite reflectance, maceral composition, porosity, and permeability, as well as gas and element composition. The Dawuba Formation could be divided into four members. In general, the shale in the first and third members showed similarly high organic matter content with most samples in range of 2–2.5% and higher brittle mineral content with a content of quartz 40.53% and 33.21%, respectively, compared with the other two members, as well as high gas content. However, the first member shale samples exhibited much higher porosity and permeability than the third member shale samples. Furthermore, the shale gas in the first member was chiefly composed of methane (average: 83.63%), while that in the third member mainly consisted of nitrogen (average: 79.92%). Hence, the first member should be regarded as the most favorable target.
Integrated MicroRNA Expression Profile Reveals Dysregulated miR‐20a‐5p and miR‐200a‐3p in Liver Fibrosis
Authors: Ye Mu , Wang Sheng , Sun Peilong , Qie Jingbo
Published: June 2021

MicroRNAs (miRNAs) have been demonstrated to involve in liver fibrogenesis. However, the miRNA‐gene regulation in liver fibrosis is still unclear. Herein, the miRNA expression profile GSE40744 was obtained to analyze the dysregulated miRNAs between liver fibrosis and normal samples. Then, we predicted the target genes of screened miRNAs by miRTarBase, followed by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Then, the protein‐protein interaction (PPI) network was constructed to identify the functional miRNA‐gene regulatory modules. Furthermore, we verified the hub gene expression using the gene expression profile GSE14323. Finally, 89 DEMs were identified in fibrotic liver samples compared to normal liver samples. The top 3 upregulated DEMs (miR‐200b‐3p, miR‐200a‐3p, and miR‐182‐5p) and downregulated DEMs (miR‐20a‐5p, miR‐194‐3p, and miR‐148a‐3p) were further studied. 516 and 1416 target genes were predicted, respectively. KEGG analysis demonstrated that the predicted genes were enriched in the p53 signaling pathway and hepatitis B, etc. Through constructing a PPI network, the genes with the highest connectivity were identified as hub genes. Of note, most of the hub genes were potentially targeted by miR‐20a‐5p and miR‐200a‐3p. Based on the data from GSE14323, the expression of EGFR, STAT3, CTNNB1, and TP53 targeted by miR‐200a‐3p was significantly downregulated in fibrotic liver samples. Oppositely, the expression of PTEN, MYC, MAPK1, UBC, and CCND1 potentially targeted by miR‐20a‐5p was significantly upregulated. In conclusion, it is demonstrated that miR‐20a‐5p and miR‐200a‐3p were identified as the novel liver fibrosis‐associated miRNAs, which may play critical roles in liver fibrogenesis.