Mathematical Models for Statistical Analysis and Control of the Float Process

2004 ◽  
Vol 61 (5/6) ◽  
pp. 135-138
Author(s):  
R. I. Makarov ◽  
V. V. Tarbeev ◽  
A. V. Molodkin ◽  
V. N. Chuplygin
Author(s):  
V. A. Gorichny ◽  
D. Yu. Serdukov ◽  
A. V. Yazenok ◽  
A. V. Nosov ◽  
G. G. Zagorodnikov ◽  
...  

An outpatient examination of 530 employees engaged in work with chemical weapons related to organophosphorus compounds at chemically hazardous facilities was carried out. Risk factors for the development of cardiovascular diseases of atherogenic etiology among personnel of the facilities were studied in relation to the type of work performed using statistical analysis methods. When assessing the lipidogram, a high incidence of atherogenic dyslipidemia in a group of personnel involved in the storage of chemical weapons was found out in comparison with a group of people engaged in the destruction and control of chemical weapons (73.1 vs 61.2 vs 59.6%, p


2021 ◽  
Vol 10 (11) ◽  
pp. 2355
Author(s):  
Dean Decter ◽  
Nissim Arbib ◽  
Hila Markovitz ◽  
Daniel S. Seidman ◽  
Vered H. Eisenberg

We compared the prevalence of ultrasound signs of adenomyosis in women with endometriosis who underwent surgery to those who were managed conservatively. This was a retrospective study of women evaluated at a tertiary endometriosis referral center who underwent 2D/3D transvaginal ultrasound. Adenomyosis diagnosis was based on the presence of at least three sonographic signs. The study group subsequently underwent laparoscopic surgery while the control group continued conservative management. Statistical analysis compared the two groups for demographics, symptoms, clinical data, and sonographic findings. The study and control groups included 244 and 158 women, respectively. The presence of any, 3+, or 5+ sonographic signs of adenomyosis was significantly more prevalent in the study group (OR = 1.93–2.7, p < 0.004, 95% CI; 1.24–4.09). After controlling for age, for all findings but linear striations, the OR for having a specific feature was higher in the study group. Women in the study group with ≥ 5 sonographic signs of adenomyosis had more than twice the risk of experiencing infertility (OR = 2.31, p = 0.012, 95% CI; 1.20–4.45). Sonographic signs of adenomyosis are more prevalent in women with symptomatic endometriosis who underwent surgery compared with those who continued conservative management. Women with 5+ findings have a significantly increased risk of infertility. Adenomyosis on ultrasound should be considered in the management decisions regarding these patients.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ahmed S. Elgazzar

Abstract The novel COVID-19 pandemic is a current, major global health threat. Up till now, there is no fully approved pharmacological treatment or a vaccine. Also, its origin is still mysterious. In this study, simple mathematical models were employed to examine the dynamics of transmission and control of COVID-19 taking into consideration social distancing and community awareness. Both situations of homogeneous and nonhomogeneous population were considered. Based on the calculations, a sufficient degree of social distancing based on its reproductive ratio is found to be effective in controlling COVID-19, even in the absence of a vaccine. With a vaccine, social distancing minimizes the sufficient vaccination rate to control the disease. Community awareness also has a great impact in eradicating the virus transmission. The model is simulated on small-world networks and the role of social distancing in controlling the infection is explained.


2018 ◽  
Vol 5 (4) ◽  
pp. 92 ◽  
Author(s):  
Kathryn Huyvaert ◽  
Robin Russell ◽  
Kelly Patyk ◽  
Meggan Craft ◽  
Paul Cross ◽  
...  

Diseases that affect both wild and domestic animals can be particularly difficult to prevent, predict, mitigate, and control. Such multi-host diseases can have devastating economic impacts on domestic animal producers and can present significant challenges to wildlife populations, particularly for populations of conservation concern. Few mathematical models exist that capture the complexities of these multi-host pathogens, yet the development of such models would allow us to estimate and compare the potential effectiveness of management actions for mitigating or suppressing disease in wildlife and/or livestock host populations. We conducted a workshop in March 2014 to identify the challenges associated with developing models of pathogen transmission across the wildlife-livestock interface. The development of mathematical models of pathogen transmission at this interface is hampered by the difficulties associated with describing the host-pathogen systems, including: (1) the identity of wildlife hosts, their distributions, and movement patterns; (2) the pathogen transmission pathways between wildlife and domestic animals; (3) the effects of the disease and concomitant mitigation efforts on wild and domestic animal populations; and (4) barriers to communication between sectors. To promote the development of mathematical models of transmission at this interface, we recommend further integration of modern quantitative techniques and improvement of communication among wildlife biologists, mathematical modelers, veterinary medicine professionals, producers, and other stakeholders concerned with the consequences of pathogen transmission at this important, yet poorly understood, interface.


2016 ◽  
Vol 09 (03) ◽  
pp. 1650045 ◽  
Author(s):  
Mianmian Zhang ◽  
Yongping Zhang

Lotka–Volterra population competition model plays an important role in mathematical models. In this paper, Julia set of the competition model is introduced by use of the ideas and methods of Julia set in fractal geometry. Then feedback control is taken on the Julia set of the model. And synchronization of two different Julia sets of the model with different parameters is discussed, which makes one Julia set change to be another. The simulation results show the efficacy of these methods.


Author(s):  
G. Tunnicliffe Wilson ◽  
H. Akaike ◽  
T. Nakagawa

2017 ◽  
Vol 5 (1) ◽  
Author(s):  
Sahara Sahara ◽  
Dedeh Kurniasih ◽  
Rizmahardian Azhari Kurniawan

ABSTRACT The process of learning chemistry which only focused on teacher as informant caused the students’ memory lower. This could make the students’ learning outcomes lower, thus, it was needed STAD type of Cooperative Learning Method which had the process of interaction between student and teacher, and could help the students comprehend the material. Therefore, it was necessary to make a research which had the purpose to know the difference between students’ learning outcomes and memory which used STAD type ofCooperative Learning Method and lectures teaching method as well as how large the effect of STAD type of Cooperative Learning Method on salt hydrolysis material was. This research was Quasi Experimental Nonequivalent Control Group Design. The sample of the research was choosen by using saturated sampling which XI IPA 1 as experimental class and XI IPA 2 as control class. The techniques of data collection used measurement technique, observation, and interview while the tools of data collection used tests such as essayquestion, observation sheet, and interview guide. The statistical analysis of posttest result using U-man whitney test obtained significant value 0.000. This value was smaller than α (0.005) which meant that there was difference in learning outcome between experimental and control class. The statistical analysis result of U-man whitney delayed test obtained significant value 0.006, this value was smaller than α (0.005) which meant that there was difference between students’ memory in experimental and control class. The calculation of effect size showed value 1.64 with high criteria which gave high effect on students’ learning outcomes which was 44.95%, while the calculation of students’ memory effect size showed value 0.69 with moderate criteria which gave effect on students’ memory which was 26,42%. Keywords : Memory, Learning Outcomes, Salt Hydrolysis, STAD type of Cooperative Learning Method


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