bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nonlinear Dynamic Analysis of Shale Gas Engine Combustion Stability
Authors: Liu Shuai , Zhang Libin , Wang Zhong , Hua Lun , Zhang Qiushi 
Published: February 2021

Abstract
The traditional analysis method of engine combustion cycle variation is a statistical method based on a small amount of data. In essence, the obtained cycle variation is random data. In order to reveal the dynamic nature of the cyclical changes during the combustion of a shale gas engine, a nonlinear dynamics method was used to study the stability of the combustion process. The motion law of the phase space trajectory is analyzed, the influence of the shale gas composition on the trajectory distribution is analyzed, the return mapping point of the average indicated pressure in the cylinder is discussed. The relationship between adjacent combustion characteristic parameters is studied; the chaotic characteristics of the shale gas engine combustion process are discussed. The results show that during the working process of the shale gas engine, the in-cylinder pressure shows a similar quasi-periodic state in the entire phase space, and the working process has a certain chaotic law; with the increase of the CH4, N2 and CO2 content in the shale gas, the combustion cycle variation increases, and the randomness of the engine working process increases. The phase space trajectory shows a monotonously increasing distribution of Poincaré mapping points on the ∑XY+ section. With the increase of the combustion cycle, the linear relationship of the scattered points gradually increases, and the randomness of the combustion process increases. The return map points of the engine combustion characteristic parameters are distributed in a cluster. When the CH4 content increases, the distribution range of the average indicated pressure return map points increases. With the increase of N2 and CO2 content, abnormal combustion phenomena such as partial combustion or misfire occur during the engine combustion process, the uncertainty of the combustion process increases, and the combustion stability decreases. With the increase of engine speed, the correlation dimension and the maximum Lyapunov exponent increase, the randomness of the combustion process increases, and the chaotic characteristics of the engine working process are obvious; the time series of the cylinder pressure is more sensitive to the content of inert gas. With the increase of N2 and CO2 content in the gas, the correlation dimension and the maximum Lyapunov exponent increase significantly, the complexity of the phase space trajectory increases, and the chaotic characteristics become more obvious.
The Review of Ecological Network Indicators in Graph Theory Context: 2014-2019
Authors: Darabi Hassan , Hashemi Rastgar , Lotfi Faroq 
Published: February 2021

Abstract
Ecological Network Analysis (ENA) capability has led to develop a set of indicators. Ecological Network Indicators (ENIs) investigates a range of subject in different context “e.g. Graph theory”, which is the origin of variety of questions such as following: What is the geographical distribution of studies and their relationship with each other? On what fields these studies are focused? What graph-based index or indexes have been used in the studies of ecological networks? What are the most widely used indexes in ecological studies? Accordingly, this study is to investigate the related literature between 2014 and 2019 in the framework of graph theory. To answer the mentioned question, we conducted systematic literature review. To find as many potentially eligible articles as possible, the search was performed multiple times using diverse related keywords. We identified 456 related records. After the screening process, 114 articles were left as the basis of further analysis. The results indicate that ENA applied mainly in China, USA, France. ENIs is studied more frequently among plants and mammals. We identified about 58 ENIs. But the Probability of Connectivity (PC), Integral index of connectivity (IIC) have been consistently used in most studies. Also, these two indices are used in combination with others ENIs. The outcomes show researchers introduce new indexes every year. The increasing trend of introducing new indicators shows the usability and applicability ENIs. But so far, PC, IIC, and LCP seem to be the most credible graph-based indexes for use in ecological network research. The overall results imply that graph theory as base of ecological network is developing, presents new indicators and opening new dimensions in the study and analysis of connections and communications in ecological networks. It has adequate flexibility to answer questions that may arise in the future in the field of ecological network analysis.
Clinical and Pathological Characteristics of Young Female Breast Cancer
Authors: Zheng Dan , Luo Ting , Zhong Xiaorong , Wang Chengshi , He Ping , Tian Tinglun , Wang Yanping , Zheng Hong 
Published: February 2021

Abstract
BackgroundWith the increase in socioeconomic status and development of early screening technologies, the proportion of young breast cancer has gradually increased. However, epidemiological research on breast cancer in young women is lagging. There is a lack of diagnosis and treatment guidelines specifically for young breast cancer patients. MethodsThis is an single-center, retrospective cohort study which adopted 2,142 women ≤ 41 years who were diagnosed with stage I-III invasive breast cancer. Patients were grouped into hormone receptor-positive and -negative groups. Variance of common characteristics between the two groups were compared using Chi-square test, Fisher-exact test and Wilcoxon rank sum test. Cox proportional hazards regression was employed for survival estimation and Kaplan–Meier curves were used to graphically present the survival data. Propensity score matching was used to balanced covariates between patients who received or not received the same treatment. ResultsThe median age of the whole cohort was 37 (16-40), and 75.0% suffered from hormone receptor (HR) positive tumors. Modified radical mastectomy was the most frequent surgery (77.7%), and 78.7% women received adjuvant chemotherapy. Adjuvant radiotherapy was implemented in 39.0% of patients, and 58.3% women did not receive radiotherapy. The HR-positive status independently predicted unfavorable overall survival (OS, HR = 1.50, 95% CI 1.03-2.21, P = 0.04) and invasive disease-free survival (iDFS, HR = 1.47, 95% CI 1.05-2.05, P = 0.02). After propensity score matching (PSM), adjuvant chemotherapy (HR = 0.47, 95% CI 0.26-0.87, P = 0.02), and adjuvant radiotherapy (HR = 0.54, 95% CI 0.37-0.78, P = 0.001) improved OS significantly. Adjuvant chemotherapy predicted favorable iDFS (HR = 0.60, 95% CI 0.38-0.94, P = 0.03). Endocrine therapy improved both OS and iDFS in patients with HR-positive disease. ConclusionThe number of young women with breast cancer is gradually increasing, and these women have worse survival outcomes than their elder counterparts. HR-positive disease predicted worse long-term survival outcomes. Adjuvant chemotherapy and adjuvant radiotherapy were required for all of the young patients. Young women with HR-positive disease can benefit from endocrine therapy. No clear benefit was seen from neoadjuvant chemotherapy in young women with early-stage breast cancer.
Climatology of Medium-Scale Traveling Ionospheric Disturbances (MSTIDs) Observed with GPS Networks in the North African Region
Authors: Oluwadare Temitope Seun , Jakowski Norbert , Valladares Cesar E. , Akala Andrew Oke-Ovie , Abe Oladipo E. , Alizadeh Mahdi M. , Schuh Harald 
Published: February 2021

Abstract
We present for the first time the climatology of medium-scale traveling ionospheric disturbances (MSTIDs) by using Global Positioning System (GPS) receiver networks on geomagnetically quiet days (Kp ≤ 3) over the North African region during 2008-2016. The ionospheric Total Electron Content (TEC) were estimated from the dual-frequency GPS measurements, and the TEC perturbations (dTEC) data were derived from the estimated TEC data. We focused on the TEC perturbations (dTEC) associated MSTIDs and statistically analyzed its characteristics, occurrence rate, diurnal and seasonal behavior as well as the interannual dependence. The results show that MSTID is a local and seasonal dependence. The results also show that MSTIDs predominantly propagates towards the South (equatorward). The daytime and nighttime MSTIDs increase with solar activity, and its event period is (12 ≤ period ≤ 53 mins), while the dominant amplitude is (0.08 ≤ amp ≤ ~1.5 dTECU). The MSTIDs propagation velocity is dominantly higher at the daytime than nighttime. The study also shows that the magnitude of MSTIDs is higher at the northwest (NW) when compared with northeast (NE), and the disturbance occurrence time is more frequent within the hours of (1200 - 1600 LT), and (1000 - 1400 LT) in December solstice at daytime for stations located in the NW and NE part of the African region, respectively. While at the nighttime, the MSTIDs also exhibits variability in disturbance occurrence time around (NW: 2100 - 0200 LT) and (NE: 1900 - 0200 LT) in June solstice, but get extended to March equinox during solar maximum (2014). The mean phase velocity in daytime MSTIDs is higher than the nighttime in every season, except during June solstice.
Fabrication and evaluation of mounted harvesting machine for sugarcane
Authors: Eldidamony Mohamed , Shal Ahmed El 
Published: February 2021

Abstract
Sugarcane is one of the important sugar crops in the world that depends on it in many industries, so we have fabricated and evaluated a machine for harvesting sugarcane to saves time, labors and costs necessary for harvesting, which is reflected in production and reduces costs. This harvester was designed for mounted on a small tractor and the single-row machine harvesting meets the functional requirements of the physical properties of the sugarcane. The performance of the harvester machine was evaluated on one shapes of cutter disc, three forward speeds and three cutter disc speeds. The results demonstrated that the average forward speed of 5 km/h, the average cutter disc speed 2000 rpm produced the lowest sugarcane losses while producing the highest power requirements and operating cost than other studied forward speeds and cutter disc speeds. It turns out that the fabricated mechanical harvester machine did not do major harm to the sugarcane and less than 6.38 % losses. Operating a sugarcane harvesting machine at optimal conditions saves time, labors and costs compared to common methods of manual harvesting.
Fixed point results in ordered bicomplex-valued metric
spaces
Authors: Abdalla Mohamed , He Fuli , Mostefaoui Zahia 
Published: February 2021

Abstract
The purpose of this paper is to state some fixed point theorems in ordered bicomplex valued
metric spaces for generalized rational type contraction mappings. Examples are given to
illustrate the results. Also, some special cases of the established results are deduced as corollaries.
ANALYSIS OF BEHAVIOR IN THE USE OF PLUG-IN HYBRID ELECTRIC VEHICLE AND HYBRID ELECTRIC VEHICLE IN THE TROPICS
Authors: Heryana Ghany , Sumarsono Danardono A. , Adhitya Mohammad , Siregar Rolan , Nazaruddin Nazaruddin , Zainuri Fuad , Prasetya Sonki 
Published: February 2021

This research aims to determine the pattern of Plug-In Hybrid Electric Vehicle (PHEV) usage and fuel consumption for the Jakarta metropolitan area, which includes the cities of Depok, Bogor, Tangerang, Bekasi, and Jakarta itself. Tests were carried out for approximately three months, with regular use. Other types of vehicles for comparison are the Internal Combustion Engine (ICE) and Hybrid Electric Vehicle (HEV) units. Fuel consumption data and vehicle usage patterns are acquired from data loggers. Economic studies are carried out in a simulation that involves the price of a vehicle, a battery, maintenance costs, and fuel prices. The results show that the best PHEV fuel consumption is for the range of 55–80 km, which is 35–40 km/liter. When compared with HEV, PHEV fuel consumption is 30 % more efficient. HEV's best fuel consumption is 22 km/liter. The ICE is far behind with 11 km/liter. However, looking at the economic side, it can be concluded that the price of PHEV is still challenging to reach for the middle class. PHEV is still classified as a luxury car for Indonesia. Assuming the amount of fuel is IDR 9,850/liter, and the vehicle service life is set at ten years, the energy cost for PHEV is around IDR 4,400–IDR 6,000/km. It is higher compare with the energy cost for a conventional car that is around IDR 3,400–IDR 3,900/km. PHEV buyers must receive incentive support from the government, not only at the time of purchase (zero tax) but also for maintenance costs and battery replacement. Indonesia has long experience in manufacturing ICE vehicles. Opening an electric vehicle industry is a strategic solution to reduce the price of these vehicles. The import tax for vehicles in Indonesia is quite high
SATURATION OF GLASS PARTICLES WITH METAL DURING SINTERING OF A COMPOSITE MATERIAL OF THE IRON–CAST IRON–GLASS SYSTEM
Authors: Jabbarov Tahir Gaffar , Aslanov Jamaladdin Nuraddin , Shahmarova Rafiga Sakhavat 
Published: February 2021

Sintering of multicomponent systems is characterized by a number of features, consisting in the fact that sintering of dissimilar materials is a complex eutectic process. Along with self-diffusion, which causes the transfer of mass to the contact area of the particles, there is mutual diffusion, which ensures the homogenization of the composition by equalizing the concentrations of unlike atoms within the sample. Under conditions of limited solubility or complete insolubility of the components, sintering of the system is complicated by the isolation of homogeneous particles from mutual contact, hindering self-diffusion and thereby worsening the sintering conditions.
The saturation of particles of vacuum glass brand S88–5 (GOST 11.027.010–75, Russia) and glass “Pyrex” (TS, Russia), which are part of iron and “iron-cast iron glass” materials, depending on the sintering temperature, has been studied.
To improve the interfacial interaction, and, consequently, to increase the mechanical and tribotechnical properties of powdered iron-glass materials, the effect of the glass melting temperature on the saturation of glass with metal was investigated. The dependences of the content of base metal and silicon ions in glass on the sintering temperature are plotted. The effect of the glass melting temperature on increasing the saturation of glass with metal is predicted.
The saturation of the glass with the base metal depends on the viscosity of the glass at sintering temperatures and is accompanied by an increase in microhardness and refractive indices up to 1.2 times compared to the initial state of the glass.
The microhardness of particles of vacuum glass of grade S88-5 after sintering of metal-glass samples increases noticeably than in samples with Pyrex glass.
When sintering "iron-cast iron-glass" materials, the metal base is saturated with silicon, which leads to an increase in the hardness of iron up to 1.8 times
Developing the Conceptual Model of Imperfect Competition Impact on Labour Reproduction and the System of Measures Aimed at its State Regulation
Authors: Makekadyrova A. S. , Kravtsevich S. V. 
Published: February 2021

Social and labour relations on today’s home labour market are accompanied by adverse social and economic phenomena, such as poverty of working population, inequality in profit distribution, discrimination in remuneration, shadow forms of employment and pay, illegal and interregional migration, labour exploitation, staff deficit and excess, which results in imperfect nature of competition on home labour market. These adverse phenomena are caused, on the one hand, by imperfect indications of competitive behavior of labour market entities, which shows the imperfect type of social and labour relations where parties’ interests are deprived of mutually beneficial basis of their satisfaction and, on the other hand, by imperfect competitive conditions of labour market entities’ functioning, which is manifested in requirements to labour quality. The article studies the key aspects of imperfect competition on home labour market and shows dynamics of its principles statistics. By analyzing and summarizing the dynamics of competitive situations investigated in the regional aspect the authors gained a conceptual model of imperfect competition taking into account its behavioral and institutional aspects. The key social and economic aspects of imperfect competition impact on labour reproduction were researched. On the basis of the provided conclusions the authors put forward certain measures of state regulation of imperfect competition, which could increase workers’ competitiveness and therefore improve the quality of labour reproduction.
Fast and Accurate Detection of COVID-19 Along With 14 Other Chest Pathologies Using a Multi-Level Classification: Algorithm Development and Validation Study
Authors: Albahli Saleh , Yar Ghulam Nabi Ahmad Hassan 
Published: February 2021

BackgroundCOVID-19 has spread very rapidly, and it is important to build a system that can detect it in order to help an overwhelmed health care system. Many research studies on chest diseases rely on the strengths of deep learning techniques. Although some of these studies used state-of-the-art techniques and were able to deliver promising results, these techniques are not very useful if they can detect only one type of disease without detecting the others.ObjectiveThe main objective of this study was to achieve a fast and more accurate diagnosis of COVID-19. This study proposes a diagnostic technique that classifies COVID-19 x-ray images from normal x-ray images and those specific to 14 other chest diseases.MethodsIn this paper, we propose a novel, multilevel pipeline, based on deep learning models, to detect COVID-19 along with other chest diseases based on x-ray images. This pipeline reduces the burden of a single network to classify a large number of classes. The deep learning models used in this study were pretrained on the ImageNet dataset, and transfer learning was used for fast training. The lungs and heart were segmented from the whole x-ray images and passed onto the first classifier that checks whether the x-ray is normal, COVID-19 affected, or characteristic of another chest disease. If it is neither a COVID-19 x-ray image nor a normal one, then the second classifier comes into action and classifies the image as one of the other 14 diseases.ResultsWe show how our model uses state-of-the-art deep neural networks to achieve classification accuracy for COVID-19 along with 14 other chest diseases and normal cases based on x-ray images, which is competitive with currently used state-of-the-art models. Due to the lack of data in some classes such as COVID-19, we applied 10-fold cross-validation through the ResNet50 model. Our classification technique thus achieved an average training accuracy of 96.04% and test accuracy of 92.52% for the first level of classification (ie, 3 classes). For the second level of classification (ie, 14 classes), our technique achieved a maximum training accuracy of 88.52% and test accuracy of 66.634% by using ResNet50. We also found that when all the 16 classes were classified at once, the overall accuracy for COVID-19 detection decreased, which in the case of ResNet50 was 88.92% for training data and 71.905% for test data.ConclusionsOur proposed pipeline can detect COVID-19 with a higher accuracy along with detecting 14 other chest diseases based on x-ray images. This is achieved by dividing the classification task into multiple steps rather than classifying them collectively.
Covid-19 risk factors and health protocol compliance among mall employees and officers in Yogyakarta
Authors: Dewi Yunita Kemala , Probandari Ari 
Published: February 2021

Purpose: This study aimed to analyze risk factors, compliance with health protocols, and the COVID-19 screening test among mall employees at Yogyakarta city, Indonesia.Methods: We analyzed secondary data from a cross-sectional study in Yogyakarta City from May-August 2020. The population was all employees at all malls in Yogyakarta City who participated in the screening rapid test zero survey conducted by the Yogyakarta City Government. Results: Bivariate analysis showed a significant relationship between ensuring proper mask install (OR = 6.33, p = 0.023, 95% CI = 1.03-38.81), applying a minimum distance of > 1 meter when outside home (OR = 27.34, p = 0.001, 95% CI = 3.01-248.32) and applying a minimum distance of > 1 meter when at work (OR = 22.25, p = 0.003, 95% CI = 2,45-201.65) with the reactive COVID-19 results. Multivariate analysis showed the most dominant variable associated with the reactive rapid test results is not keeping a minimum distance of > 1 meter when outside the house with a value of (OR=11.91, p=0.047, 95% CI = 1.03-137.37). Conclusion: The risk factor for Covid-19 for employees and mall staff is physical distancing > 1 meter when outside the house. The city administration should keep working with mall managers to tighten health protocols in malls and other public areas to prevent Covid-19 transmission.
RECONSTRUCTION OF PROSTITUTION LAW IN PERSPECTIVE OF RELIGIOUS NORMS AND RENEWAL OF CRIMINAL LAW
Authors: Rofiq Noor Fajari 
Published: February 2021

Cases of prostitution as the subject of commercial sex workers (Pekerja Sex Komersial) and sex service users until now are free to undergo without the threat of punishment. Until now, there has been no rule that can punish prostitutes or prostitutes and their customers .then there needs to be a legal reconstruction to achieve a responsive law then need to reform the law to achieve the law in the goal. This research aimed to know and understand the Construction of Prostitution Crimes in the Criminal Code, and The Penal Code Bill is associated with Religious Norms. And Know and understand the Construction of Formulation of Prostitution Crimes that are Ideal and in line with religious norms for Indonesian society, as for normative juridical research methods. The approach used in this writing is a statutory approach or (statute approach) and the analytical and conceptual approach analysis of legal concepts. The results show that it is necessary to explore the concept of philosophical, sociological, and juridical basic values that the state to have legal certainty in society in the Criminal War draft stage. So digging into the philosophical value of the 1st Pancasila, The One Godhead (Ketuhanan yang Maha Esa), the five religions apply in Indonesia, including Islam, Christianity, Catholicism, Hindu, Buddha, and Confucian has asserted that the practice of prostitution is legally prohibited.