bluuebunny/crossref_metadata_2025_split huggingface dataset:
Acceleration of a ball down an inclined plane
Authors: Cross Rod 
Published: February 2021

Abstract
A standard problem for physics students is to calculate or measure the acceleration of an object down an inclined plane. Additional information can be obtained by measuring the angular acceleration as well as the linear acceleration. An experiment is described where a billiard ball was filmed as it rolled down an inclined plane at different inclination angles. The transition from rolling without slipping to rolling with slipping was identified, and the relevant friction coefficients were measured independently from the linear and angular accelerations.
An unsupervised 2D–3D deformable registration network (2D3D-RegNet) for cone-beam CT estimation
Authors: Zhang You 
Published: February 2021

Abstract
Acquiring CBCTs from a limited scan angle can help to reduce the imaging time, save the imaging dose, and allow continuous target localizations through arc-based treatments with high temporal resolution. However, insufficient scan angle sampling leads to severe distortions and artifacts in the reconstructed CBCT images, limiting their clinical applicability. 2D–3D deformable registration can map a prior fully-sampled CT/CBCT volume to estimate a new CBCT, based on limited-angle on-board cone-beam projections. The resulting CBCT images estimated by 2D–3D deformable registration can successfully suppress the distortions and artifacts, and reflect up-to-date patient anatomy. However, traditional iterative 2D–3D deformable registration algorithm is very computationally expensive and time-consuming, which takes hours to generate a high quality deformation vector field (DVF) and the CBCT. In this work, we developed an unsupervised, end-to-end, 2D–3D deformable registration framework using convolutional neural networks (2D3D-RegNet) to address the speed bottleneck of the conventional iterative 2D–3D deformable registration algorithm. The 2D3D-RegNet was able to solve the DVFs within 5 seconds for 90 orthogonally-arranged projections covering a combined 90° scan angle, with DVF accuracy superior to 3D–3D deformable registration, and on par with the conventional 2D–3D deformable registration algorithm. We also performed a preliminary robustness analysis of 2D3D-RegNet towards projection angular sampling frequency variations, as well as scan angle offsets. The synergy of 2D3D-RegNet with biomechanical modeling was also evaluated, and demonstrated that 2D3D-RegNet can function as a fast DVF solution core for further DVF refinement.
Is skin temperature associated with muscle recovery status following a single bout of leg press?
Authors: Ferreira-Júnior João B , Chaves Suene F N , Pinheiro Maria H A , Rezende Vitor H S , Freitas Eduardo D S , Marins João C B , Bara-Filho Maurício G , Vieira Amilton , Bottaro Martim , Costa Carlos M A 
Published: February 2021

Abstract

Objective. The measurement of skin temperature using infrared thermography has gained a lot of attention in sport and science since it might be related to the recovery process following high intensity, potentially damaging exercise. This study investigated the time course of the skin temperature response and the muscle recovery status following a resistance training session involving leg press exercise. Approach. Fourteen young male college students (19.9 ± 1.7 years, 176 ± 6 cm, 66.1 ± 7.6 kg, 21.1 ± 1.8 kg.m−2) performed one session involving 10 sets, of 10 repetition maximum each (RM), of unilateral leg press 45° exercise, performed to momentary muscle failure, with 2 min rest between sets. Perceived recovery, mean and maximum thigh skin temperatures, thigh muscle thickness, maximal isometric strength, muscle soreness, and horizontal jump performance were measured pre, 24, 48, and 72 h following exercise. Main results. The exercise protocol resulted in significant reduction in isometric strength, horizontal jump performance, and perceived recovery (p < 0.05). There was also a significant (p < 0.05) increase in muscle thickness and muscle soreness. With exception of jump performance, that recovered at 48 (p > 0.05), recovery parameters did not recover up to 72 h post-exercise (p > 0.05). Surprisingly, skin temperatures were not altered throughout the entire 72 h post-exercise period (p > 0.05). No significant positive correlation was found between skin temperatures and muscle thickness. Additionally, only one out of 16 correlation coefficients showed significant (r = −0.56, p = 0.036) inverse association between skin temperature and isometric strength. Significance. In conclusion, thigh skin temperature remains unaffected up to 72 h following a leg press exercise, and the time course response of thigh skin temperature was not associated with recovery status.
Notes on index of quantum integrability
Authors: Tian Jia , Hou Jue , Chen Bin 
Published: February 2021

Abstract
A quantum integrability index was proposed in Komatsu et al (2019 SciPost Phys.
7 065). It systematizes the Goldschmidt and Witten’s operator counting argument (Goldschmidt and Witten 1980 Phys. Lett. B 91 392) by using the conformal symmetry. In this work we compute the quantum integrability indexes for the symmetric coset models

SU
(
N
)

/

SO
(
N
)

and

SO
(
2
N
)

/

SO
(
N
)
×
SO
(
N
)

. The indexes of these theories are all non-positive except for the case of

SO
(
4
)

/

SO
(
2
)
×
SO
(
2
)

. Moreover we extend the analysis to the theories with fermions and consider a concrete theory: the

CP

N

model coupled with a massless Dirac fermion. We find that the indexes for this class of models are non-positive as well.
A proposal for assessing the uncertainty in the measurement of mean nanoparticle diameter with electron microscopy
Authors: Lira I 
Published: February 2021

Abstract
Of paramount importance in the field of nanotechnology is the ability to measure reliably the properties of nanomaterials, especially their size. In general, just an estimate of size is not sufficient: a quantitative indication of the estimate’s quality in the form of an assessment of its uncertainty is necessary as well. For example, standard ISO/IEC 17025:2017 (general requirements for the competence of testing and calibration laboratories) stipulates that appropriate methods and procedures shall be used for laboratory activities and for the analysis of data, including the identification and quantification of all contributions to the measurement uncertainties. In order to facilitate compliance with requirements such as these, a procedure is proposed for assessing the uncertainty in the evaluation of the mean area-equivalent diameter of a nanoparticle population by scanning electron microscopy. We take as reference the general approach proposed in the guide to the expression of uncertainty in measurement, which is globally seen as the de facto standard for the evaluation of measurement uncertainty, and as such, it is normally required for accreditation. Thus, the proposed approach, primarily intended for guidance, will hopefully be found practical, understandable and useful. Ideally, it should be validated, and perhaps improved, through international intercomparison exercises.
Evaluation of blackbody radiation shift with 2 × 10−18 uncertainty at room temperature for a transportable 40Ca+ optical clock
Authors: Zhang Ping , Cao Jian , Yuan Jin-bo , Liu Dao-xin , Yuan Yi , Wei Yuan-fei , Shu Hua-lin , Huang Xue-ren 
Published: February 2021

Abstract
Blackbody radiation (BBR) temperature and its uncertainty mainly contribute to the BBR shift uncertainty, which is one of the challenges in most ion optical clocks. Here, an improved BBR temperature evaluation method based on the analysis of the effective solid angle of an ion trapping system using the finite element method is presented. To effectively suppress the BBR temperature uncertainty, the structure of an ion trap was optimized to reduce the effective solid angle of the insulating supports, and a BBR shield was employed to reduce the influence of the surrounding BBR in the newly developed ion trap system. Due to radiofrequency field, it is difficult to evaluate the temperature of BBR shield accurately using contact-temperature-sensors inside the vacuum chamber. We used a well shielded platinum resistance temperature sensor to measure the temperature of the shield from the outside of the vacuum chamber. Through a detailed evaluation, the BBR temperature uncertainty of this newly designed system is 0.17 K, corresponding to a BBR frequency shift uncertainty of 2 × 10−18 for the 40Ca+ optical clock. This improvement of the BBR temperature uncertainty using the active adjustment of the distribution of the effective solid angle of the ion trapping system, without a complicated cryogenic trap, is very suitable for transportable optical clocks operating at room temperature (∼295 K).
Analysis of Quality Control of Chicken Nugget Products by Using Six Sigma Method at PT. XYZ
Authors: Irawan Neldo , Ratnawati Anny , Dilla Salsa 
Published: February 2021

AbstractPT. XYZ is a company that produces chicken nugget. The company faces quality problems, namely the discovery of defective products. The purpose of this research was to identify and analyze the factors causing the occurrence of defective products in the chicken nugget production process; analyze product quality and propose improvements in improving product quality. The data collection techniques used were interviews, observations and documentation conducted for 1 month on February 13, 2020 to March 13, 2020. The Six Sigma method chosen in this study as an approach to the problem that consists of 5 stages, namely, Define, Measure, Analyze, Improve and Control. The value of Six Sigma for each process was 3.69 (Industry average in Indonesia) for the selection and preparation of raw materials, 4.1(Industry average in Indonesia) dough cutting process and 4.3 (Industry average in USA) for the coating process of cuts. The proposed strategy is divided into 6 short-term proposals and 4 long-term proposals. If this defect product problem is solved, it can maintain the brand image, reputation, profitability, and sustainability of the company. Some proposed improvements that have been applied were found to decrease the number of defects as much as 48% in dough cutting process and coating of cuts. In addition, the company could potentially maximize profits by by cutting losses by approximately 8 million rupiah/year.
YOLOv3_Slim for Face Mask Recognition
Authors: Jiang Xiaoming , Xiang Fugui , Lv Minghong , Wang Wei , Zhang Zhonghua , Yu Yi 
Published: February 2021

Abstract
The use of face mask is advised by World Health Organization (WHO) for preventing transmission of Coronavirus disease 2019 (COVID-19). It is of great value to solve the multi-task object detection problem of non-wearing mask, wrong way wearing mask and standard wearing mask. In this paper, a network YOLOv3_Slim based on YOLOv3 is implemented. It’s faster than YOLOv3. Detection speed increased from 15.67 fps to 16.89 fps. In the mean time, we found the effect of the difference of inner class on the classification ability of the model. The large error of inner class will reduce the accuracy of the model and make the attention mechanism ineffective. So after changing the labels of the third data set, We add ECA module to our network. YOLOv3_Slim is more accurate than YOLOv4 in face mask recognition based on our data set. The mAP increased from 89.45% to 92.50%.
End-to-end bone age assessment based on Attentional Region Localization
Authors: Yang Chunde , Liu Qingshui , Li Zhangyong , Wang Wei , Li Xinwei 
Published: February 2021

Abstract
Pediatric bone age assessment (BAA) is an extremely important clinical method to investigate endocrinology, genetic and growth disorders of adolescents. The current deep learning-based BAA scheme generally feeds the images into the training model, but ignores the local details of the skeleton images and does not exclude the noise around the images. Many methods train segmentation or detection networks to exploit local information, but requires a lot of manual annotation and additional costs. In this paper, we proposed an attentional region localization method for BAA to automatically localize the hand region and local regions without any additional annotations. First, an attentional hand location module (AHLM) was used to obtain a clearer hand region, which eliminates the interference noise of the original image. Then an attentional region generation module (ARGM) was used to extract the local attentional regions with high discriminant features, which can help to optimize the entire network framework. We integrate the entire network into an end-to-end structure by jointly optimizing the network through a shared backbone and fully connected layers. The effectiveness of the proposed attentional region localization method was evaluated on an open dataset Radiological Society of North America (RSNA) with an average absolute error (MAE) of 6.14, which performs better than most existing methods.
An Exploration on Using Mobile Smart Terminals to Promote the Reform of College English Teaching and Learning
Authors: Zhao Jianglian 
Published: February 2021

Abstract
College English is a compulsory basic course for higher education in China. At the same time, handling a secondary language is a must-have under the globalization. However, the students’ English proficiency has always been unsatisfactory after so many years of teaching and learning. Meanwhile, in the era of information and data, Internet has not only changed our country’s economic model, but also brought a revolution in education. Nowadays, Every college student has a mobile smart terminal at least, and we can make full use of this device to improve the teaching methods and even implement it into classrooms. Based on this opportunity, this article explores how to use mobile smart devices to improve the traditional “teaching” and “learning” for non-English majors in universities.
Osteogenic differentiation system based on biopolymer nanoparticles for stem cells in simulated microgravity
Authors: Zhao Xiao-Hong , Peng Xue-Liang , Gong Hai-Lun , Wei Dai-Xu 
Published: February 2021

Abstract
An efficient long-term intracellular growth factor release system in simulated microgravity for osteogenic differentiation was prepared based on polylactic acid (PLA) and polyhydroxyalkanoate (PHA) nanoparticles (NPs) for loading of bone morphogenetic protein 2 (BMP2) and bone morphogenetic protein 7 (BMP7) (defined as sB2-PLA-NPs and sB7-PHA-NPs), respectively, associated with osteogenic differentiation of human adipose derived stem cells (hADSCs). On account of soybean lecithin (SL) as biosurfactants, sB2-PLA-NPs and sB7-PHA-NPs had a high encapsulation efficiency (>80%) of BMPs and uniform small size (<100 nm), and showed a different slow-release to provide BMP2 in early stage and BMP7 in late stages of osteogenic differentiation within 20 d, due to degradation rate of PLA and PHA in cells. After uptake into hADSCs, by comparison with single sB2-PLA-NPs or sB7-PHA-NPs, the Mixture NPs compound of sB2-PLA-NP and sB7-PHA-NP with a mass ratio of 1:1, can well-promote ALP activity, expression of OPN and upregulated related osteo-genes. Directed osteo-differentiation of mixture NPs was similar to result of sustained free-BMP2 and BMP7-supplying (sFree-B2&B7) in simulated microgravity, which demonstrated the reliability and stability of Mixture NPs as a long-term osteogenic differentiation system in space medicine and biology in future.
Defining El Niño indices in a warming climate
Authors: van Oldenborgh Geert Jan , Hendon Harry , Stockdale Timothy , L’Heureux Michelle , Coughlan de Perez Erin , Singh Roop , van Aalst Maarten 
Published: February 2021

Abstract
Extreme weather and climate events associated with El Niño and La Niña cause massive societal impacts. Therefore, observations and forecasts are used around the world to prepare for such events. However, global warming has caused warm El Niño events to seem bigger than they are, while cold La Niña events seem smaller, in the commonly used Niño3.4 index (sea surface temperature (SST) anomalies over 5∘ S–5∘ N, 120–170∘ W). We propose a simple and elegant adjustment, defining a relative Niño3.4 index as the difference between the original SST anomaly and the anomaly over all tropical oceans (20∘ S–20∘ N). This relative index describes the onset of convection better, is not contaminated by global warming and can be monitored and forecast in real-time. We show that the relative Niño3.4 index is better in line with effects on rainfall and would be more useful for preparedness for El Niño and La Niña in a changing climate and for El Niño—Southern Oscillation research.
A comparative analysis of different terrain correction methods based on Landsat-8 OLI data
Authors: Zhang Ying , Ai Yunfei , Su Fei , Su Hang , He Zhixian , Wang Changhai , Ying Jun , Zhou Minlu 
Published: February 2021

Abstract
The topographic effect has long been recognized as one of problems for quantitative remote sensing. The paper compares the correction results of OLI data based on C model, Cosine model, SCS model, Minnaert model and pixel-based Minnaert Correction Method. The visual inspection, statistical analysis and regression analysis of images were used to analyze the results before and after correction of image. The results show that the C model has a better correction effect. The Cosine model and SCS model were significantly overcorrected. However, C model, Minnaert model and slope-based Minnaert model weakened the influence of terrain. By comparative analysis, the C correction method was optimal model for OLI image.
Numerical analysis of influence of joint inclination on the stability of high rock slope with weak interlayer
Authors: Wang Lei , Qi Yuna , Wang Wei , Su Zhandong 
Published: February 2021

Abstract
In the mountainous area of southwest China, the horizontal layered steep slopes with weak intercalations are widely distributed. The stability of these slopes is often controlled by the weak intercalations and the dominant joint sets. Based on the strength reduction method, a representative numerical simulation model is established in this study, and the ubiquitous-joint model is adopted in which the properties of rock blocks and joints can both be considered, in order to analyze the influence of joint angle on slope stability and potential sliding surface of such slopes. The research results indicate that the joint inclination angle is closely related to both the safety coefficient and the potential sliding range of the slope. With the increase of joint inclination angle, the safety coefficient of the slope decreases, but the downward trend gradually becomes slower. The joint inclination angle also has an obvious influence on the sliding surface range of the horizontal layer slope with weak interlayer. The research results have certain guiding significance in the analysis of failure mechanism, hazard assessment and engineering prevention of this kind of slope.
Characteristics of fluid inclusions in the Alqal Copper-Lead-Zinc deposit, Xinjiang
Authors: Zhang Chenguang , Tang Xiangwei , Liu Kuisong , Zhou Hongxia , Yuan Dezhi , Guo Yueshan , Bao Junfan , Fan Jinwei , Zha Daohan , Yao Yuan , Ruze Yusupu , Shi Xingjun , Yan Yutong , Zhou Hongsheng 
Published: February 2021

Abstract
The Alqal Copper-lead-zinc deposit isl ocated in the Tarim plate of the Xinjiang. It has undergone multiple stages of tectonic mineralization and is an important deposit in the Kuslafu metallogenic belt of the West Kunlun area. Based on the analysis of the metallogenic geological conditions of the deposit, The composition of fluid inclusions in mining area was studied, The characteristics of metallogenic fluid are discussed. The results show that the uniform temperature of gas-liquid two-phase fluid inclusions in the Alqal deposit is between 145°C and 267°C, the average uniform temperature is 191°C; the salinity is 0.71% to 14.87%, and the average salinity is 6.33%. The estimated metallogenic pressure is about 135MPa, and the capture temperature is concentrated around 320°C. The ore-forming fluid has undergone multi-stage superimposed transformation, which is inconsistent with the characteristics of the typical MVT deposit, and it is a sedimentary transformation type deposit.
Reconstruction of Palaeoglacier in the Qugaqie valley in Nyainqêntanglha Range
Authors: Yao Jin , Chao-lu Yi , DanDan Xu , Nan Yang 
Published: February 2021

Abstract
Reconstruction of palaeoglacier is important for understanding the mechanism of palaeo-climatic change and predicting water resource in Tibet. The climate and water resource are sensitive to global change in western Nyainqêntanglha Range. However, the data of how glacier changed in its area and equilibrium line, particularly its volume are still in paucity. In this study, we generated the palaeoglacier landform map by field investigation and 3S (RS, GPS and GIS) technology, reconstructed the palaeoglaciers surface by glacial landforms and glacier model, accordingly estimated the ice volume and equilibrium line altitude (ELA), and then discussed the palaeo-climate during the last glacial maximum (LGM) in the Qugaqie valley. During the LGM, the Qugaqie glacier was about 18.5 km long and 102.1 m thick in average. It covered an area of 59.1 km2 and had a volume of 6.05 km3, which were 8.34 times of the area and 18.33 times of the ice volume of the modern glacier. The 75.3% of Qugaqie valley was covered by glacier. The palaeo-ELA was 5405∼5496 m with a depression of 400 to 300 m, which confirms Shi Yafeng’s point that an even global ELA lowering value of about 1000 m didn’t virtually exist.
Analyzing the wettability of tight sandstone of Taiyuan Formation in Shenfu block, eastern margin of Ordos Basin
Authors: Qin Qiang , Cheng Hanlie , Wang Minghao , Sun Ming , Zhao Li 
Published: February 2021

Abstract
Reservoir wettability is an important indicator in the study of multiphase fluids in oil reservoirs. It involves the migration of crude oil from source rocks to reservoirs, accumulation in the reservoirs, and the entire process of crude oil development. The distribution characteristics of the wettability of sandstone reservoirs can provide a certain reference for the analysis of tight sandstone oil migration and accumulation mechanisms, and the exploration and development of tight sandstone reservoirs. This paper measures the contact angle between oil and tight sandstone by using the hanging drop method. Using the KRUSS DSA100S video optical contact angle measuring instrument, 25 unwashed oil tight cores and 62 washed oil tight cores are tested, respectively. Experimental analysis shows that the contact angle of the tight sandstones of the Taiyuan Formation in the Shenfu block of the Ordos Basin ranges from 50° to 150°, and the sample contact angles are concentrated between 70° to 110°. The wettability of the reservoir is mainly of the intermediate wet type, followed by the water wet type and the oil wet type.