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Articles 62341 - 62370 of 294574

Full-Text Articles in Physical Sciences and Mathematics

Depression And Factors Impacting Quality Of Life Among Adults With Asthma Presence In Nevada, Elizabeth D. Kahane, Lung-Chang Chien, Brian Labus, Dharini M. Bhammar, Jocy-Anna Chevalier, Sheniz Moonie Mar 2022

Depression And Factors Impacting Quality Of Life Among Adults With Asthma Presence In Nevada, Elizabeth D. Kahane, Lung-Chang Chien, Brian Labus, Dharini M. Bhammar, Jocy-Anna Chevalier, Sheniz Moonie

Epidemiology & Biostatistics Faculty Research

Background: Asthma, a chronic, non-communicable disease has been shown to negatively affect mental health and quality of life among adults. Annually approximately 8% of adult Nevadans report current asthma symptoms and 12.6% report having a lifetime diagnosis. The purpose of this study was to evaluate the association between asthma and depression and explore quality of life factors affecting adult Nevadans with asthma. Methods: Using behavioral risk factor surveillance system (BRFSS) data, this study evaluated the association between self-reported asthma and depression in Nevada using weighted multiple logistic regression. BRFSS asthma call-back survey (ACBS) data were used to determine the frequency …

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Influence Of Coal Lithotypes On Adsorption/Desorption Characteristics In Coal Reservoirs And Its Practical Significance: A Case Study In Baode Block, Hou Wei, Xu Fengyin, Zhang Lei, Zhang Wei, Meng Yanjun, Liu Qihu, Li Yongchen, Fan Hongbo, Wang Hongya, Zhang Shuangyuan, Zhang Wen Mar 2022

Influence Of Coal Lithotypes On Adsorption/Desorption Characteristics In Coal Reservoirs And Its Practical Significance: A Case Study In Baode Block, Hou Wei, Xu Fengyin, Zhang Lei, Zhang Wei, Meng Yanjun, Liu Qihu, Li Yongchen, Fan Hongbo, Wang Hongya, Zhang Shuangyuan, Zhang Wen

Coal Geology & Exploration

The difference of coal lithotypes is an important factor affecting the adsorption/desorption characteristics of coalbed methane (CBM) and the productivity of CBM wells. According to four coal samples of different lithotypes from No. 8+9 Coal Seam in Well BX-2, proximate analysis, maceral, wettability and isothermal adsorption/desorption experiments are carried out, and the influence of coal lithotypes on CBM adsorption/desorption characteristics and its mechanism is discussed. The results show that vitrinite content in dull, semi-dark, semi-bright and bright coal samples increases gradually, water and ash content decreases gradually, hydrophilicity decreases gradually, and the Langmuir volume increases gradually. Bright and semi-bright coal …

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Table Of Contents, The Editors Mar 2022

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

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Progress Of Coalbed Methane Exploration And Development In China During The 13th Five-Year Plan Period And The Next Exploration Direction, Ye Jianping, Hou Songyi, Zhang Shouren Mar 2022

Progress Of Coalbed Methane Exploration And Development In China During The 13th Five-Year Plan Period And The Next Exploration Direction, Ye Jianping, Hou Songyi, Zhang Shouren

Coal Geology & Exploration

Based on survey data of coalbed methane exploration and development projects in China, the production status of coalbed methane fields and scientific & technological achievements, this paper analyzes the comprehensive control technical measures for stable and increasing production of coalbed methane fields, and the geological conditions and potential of deep coalbed methane exploration breakthrough. The coalbed methane horizontal well technology and the matching well pattern optimization and drainage technology are also summarized. The results show that the most effective technical measures for the comprehensive control of stable production of coalbed methane fields and low production wells in China are four …

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Research Progress And Development Direction Of Key Technologies For Efficient Coalbed Methane Development In China, Xu Fengyin, Yan Xia, Lin Zhenpan, Li Shuguang, Xiong Xianyue, Yan Detian, Wang Hongya, Zhang Shuangyuan, Xu Borui, Ma Xinyuan, Bai Nan, Mei Yonggui Mar 2022

Research Progress And Development Direction Of Key Technologies For Efficient Coalbed Methane Development In China, Xu Fengyin, Yan Xia, Lin Zhenpan, Li Shuguang, Xiong Xianyue, Yan Detian, Wang Hongya, Zhang Shuangyuan, Xu Borui, Ma Xinyuan, Bai Nan, Mei Yonggui

Coal Geology & Exploration

During the 13th Five Year Plan period, the major problem of the low output of a single well of coalbed methane (CBM) has restricted the efficient development of CBM in China. Through Major National Science and Technology Projects and other technical researches, significant progress has been made in the theoretical understanding and engineering technology of CBM exploration and development. It is manifested in four aspects as follows. Firstly, the exploration concept has changed from looking for rich dessert areas to high-yield dessert areas, and the extensive development deployment has become finer. Secondly, in terms of efficient stimulation technology, with the …

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Exploration And Development Process Of Coalbed Methane In Eastern Margin Of Ordos Basin And Its Enlightenment, Yang Xiuchun, Xu Fengyin, Wang Hongya, Li Shuguang, Lin Wenji, Wang Wei, Hao Shuai Mar 2022

Exploration And Development Process Of Coalbed Methane In Eastern Margin Of Ordos Basin And Its Enlightenment, Yang Xiuchun, Xu Fengyin, Wang Hongya, Li Shuguang, Lin Wenji, Wang Wei, Hao Shuai

Coal Geology & Exploration

The buried depth of coal seam in the eastern margin of Ordos Basin changes greatly, and the characteristics of coalbed methane reservoir formation and reservoir reconstruction methods vary greatly with different buried depths. At present, coalbed methane exploration gradually extends from a shallow area of 1 000 m to a deeper area of 2 000 m. To study the theory and technology of efficient exploration and development of coalbed methane resources under different burial depths, this paper reviews the exploration and development practices in the eastern margin of Ordos Basin in the past 30 years. According to the changes of …

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Review Of The Progress Of Geological Research On Coalbed Methane Co-Production, Guo Chen, Qin Yong, Yi Tongsheng, Ma Dongmin, Wang Shengquan, Shi Qingmin, Bao Yuan, Chen Yue, Qiao Junwei, Lu Lingling Mar 2022

Review Of The Progress Of Geological Research On Coalbed Methane Co-Production, Guo Chen, Qin Yong, Yi Tongsheng, Ma Dongmin, Wang Shengquan, Shi Qingmin, Bao Yuan, Chen Yue, Qiao Junwei, Lu Lingling

Coal Geology & Exploration

Coalbed methane (CBM) co-production is an important way to improve the efficiency of CBM development in multi-seam areas, but the special nature of reservoir formation makes the co-mining method and production effect complex and variable, which presents challenges for efficient development. Experts in the field of CBM from China have carried out a lot of basic research and engineering practice on CBM reservoir formation and the feasibility of co-production in multiple seams, which have gained fruitful results, providing strong support for deepening the CBM geological theory and promoting industrial development. To provide reference for subsequent research, engineering implementation and industrial …

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Research Progress Of Multi-Source And Multi-Stage Genesis Of Co2-Enriched Cbm And The Enlightenments For Its Exploration And Development, Tang Shuling, Tang Dazhen, Sun Bin, Tao Shu, Zhang Taiyuan, Pu Yifan, Zhang Aobo, Zhi Yuanhao Mar 2022

Research Progress Of Multi-Source And Multi-Stage Genesis Of Co2-Enriched Cbm And The Enlightenments For Its Exploration And Development, Tang Shuling, Tang Dazhen, Sun Bin, Tao Shu, Zhang Taiyuan, Pu Yifan, Zhang Aobo, Zhi Yuanhao

Coal Geology & Exploration

CO2-enriched coalbed methane(CBM) carries important geological information on CBM genesis and accumulation, and is closely related to the exploration and evaluation of CBM resources. On the basis of the systematic summary of the current research progress of CBM genesis, the current research status of the genetic mechanism of CO2-enriched CBM reservoirs was scientifically analyzed by dissecting the special geological examples of CO2-enriched CBM reservoirs in the southern Junggar Basin, and the problems in the research process of CBM genesis were comprehensively pointed out. The study shows that the generation of CBM has multiple sources …

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Enrichment Theory Of Large Area And High Abundance Marine Shale Gas And Its Geological Evaluation Technology Progress And Application, Wang Hongyan, Liu Dexun, Yu Yuanjiang, Zhao Qun, Qiu Zhen, Dong Dazhong, Shi Zhensheng, Sun Shasha, Jiang Zhenxue, Liu Honglin, Zhou Shangwen, Bai Wenhua Mar 2022

Enrichment Theory Of Large Area And High Abundance Marine Shale Gas And Its Geological Evaluation Technology Progress And Application, Wang Hongyan, Liu Dexun, Yu Yuanjiang, Zhao Qun, Qiu Zhen, Dong Dazhong, Shi Zhensheng, Sun Shasha, Jiang Zhenxue, Liu Honglin, Zhou Shangwen, Bai Wenhua

Coal Geology & Exploration

The enrichment characteristics and main controlling factors of marine shale gas, geological evaluation and comprehensive area selection of sweet spots are the core content and key to the breakthrough of shale gas exploration and development in Sichuan Basin and its periphery. On the basis of intensive study of geology and geophysical multidisciplinary joint research, field investigation, survey and sampling analysis of key outcrops, core observation and fine description of key exploration wells, this paper presents the enrichment theory and connotation of geological evaluation technology of large area and high abundance shale gas as well as its recent advances, field applications …

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Theoretical Basis Of Dredging And Efficient Development Of High−Rank Coalbed Methane In China: A Case Study Of The Qinshui Basin, Zhu Qingzhong Mar 2022

Theoretical Basis Of Dredging And Efficient Development Of High−Rank Coalbed Methane In China: A Case Study Of The Qinshui Basin, Zhu Qingzhong

Coal Geology & Exploration

China is rich in high-rank coalbed methane(CBM) resources, which accounts for more than 90% of the total production of CBM in China. The efficient development and utilization of high-rank coal and coalbed methane(CBM) resources is of great practical significance for ensuring national energy strategic security and helping to achieve the strategic goals of “carbon peak and carbon neutrality”. The coalbed methane industry in China is generally characterized by low exploration and development degree, poor adaptability of main technology, low rate of return on investment and small development scale. The large-scale and efficient development of coalbed methane is faced with great …

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Accumulation Model And Exploration And Development Suggestions Of Coal Measure Gas Hydrates In Sanlutian Area Of Muli Coalfield, Qinghai Province, Cao Daiyong, Qin Rongfang, Wang Anmin, Chen Limin, Li Jing, Wei Yingchun Mar 2022

Accumulation Model And Exploration And Development Suggestions Of Coal Measure Gas Hydrates In Sanlutian Area Of Muli Coalfield, Qinghai Province, Cao Daiyong, Qin Rongfang, Wang Anmin, Chen Limin, Li Jing, Wei Yingchun

Coal Geology & Exploration

The Natural Gas Hydrate(NGH) is known as the most promising strategic resource in the 21st century because of its huge energy density, convenient use, high combustion value, and cleanness, and it is an alternative energy source with huge potential for conventional oil and gas resources. The occurrence of the NGH in the Sanlutian area of Muli Coalfield in Qinghai Province is the result of the interaction between the abundant gas sources and the hydrate stability zone in cold highland areas. The NGH in coal-bearing strata is defined as the coal measure gas hydrate, belonging to unconventional coal measure gases. To …

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Difference Analysis Of Methane Diffusion Properties Between Tectonic Coal And Primary Coal, Meng Zhaoping, Zhang Kun, Shen Zhen Mar 2022

Difference Analysis Of Methane Diffusion Properties Between Tectonic Coal And Primary Coal, Meng Zhaoping, Zhang Kun, Shen Zhen

Coal Geology & Exploration

Primary coal destroyed by geological stresses will form different types of coal structures, and the accumulation and migration of coalbed methane(CBM) are affected by the changes in pore structures, adsorption/desorption, diffusion and permeability. In this paper, the methane isothermal adsorption experiment, and low-temperature liquid nitrogen and carbon dioxide adsorption experiment were carried out on the samples of primary coal and tectonic coal of No.3 coal seam of Zhaozhuang Coal Mine in Qinshui Basin, so as to analyze the adsorption/desorption properties and pore structure characteristics of primary coal and tectonic coal. The methane diffusion difference and control mechanism of primary coal …

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Physical Simulation Of In-Situ Microbial Methanation In Coal Reservoirs With The Participation Of Supercritical Co2, Su Xianbo, Wang Lufei, Zhao Weizhong, Xia Daping, Zhou Yixuan, Wang Qian Mar 2022

Physical Simulation Of In-Situ Microbial Methanation In Coal Reservoirs With The Participation Of Supercritical Co2, Su Xianbo, Wang Lufei, Zhao Weizhong, Xia Daping, Zhou Yixuan, Wang Qian

Coal Geology & Exploration

Supercritical CO2 can destroy the molecular structure of coal and increase the production of biomethane. To investigate the gas production potential under the in-situ conditions of coal reservoirs with the participation of supercritical CO2, the original reservoir pressure, reservoir temperature, and gas composition of the target coal seam in a coalbed methane block in Xinjiang were used as the in-situ reservoir conditions. The self-designed anaerobic fermentation device for coal reservoirs was used to simulate the in-situ anaerobic fermentation process, and the biogas production, coal surface functional groups and microbial community structure under the in-situ conditions were analyzed. …

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Gas Content And Productivity Controlling Factors Of Coal Reservoir In Sijiazhuang Area, Qinshui Basin, Li Guofu, Zhang Wei, Li Meng, Pan Jienan, Liu Liangliang, Chen Zhaoying, Zhang Yongcheng, Bai Yang Mar 2022

Gas Content And Productivity Controlling Factors Of Coal Reservoir In Sijiazhuang Area, Qinshui Basin, Li Guofu, Zhang Wei, Li Meng, Pan Jienan, Liu Liangliang, Chen Zhaoying, Zhang Yongcheng, Bai Yang

Coal Geology & Exploration

In order to study the characteristics of coalbed methane accumulation and production controlling factors in the northeastern Qinshui Basin, based on the data of coalbed methane drilling and drainage in the Sijiazhuang area, the geological structure, coal seam thickness and buried depth, maceral of the Sijiazhuang coals are analyzed. The geological control mechanism of gas-bearing coal reservoirs is studied, combined with the fracturing and drainage technology of coal-bed methane wells, the production characteristics of coal-bed methane and its influencing factors are discussed. The results show that: (1) The gas-bearing properties of coal reservoirs in the study area are greatly affected …

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Characteristics Of Coal Reservoirs And Favorable Areas Classification And Optimization Of Cbm Planning Blocks In Guizhou Province, Xiang Wenxin, Sang Shuxun, Wu Zhangli, Tu Bin, Guo Zhijun, Han Sijie, Zhou Xiaozhi, Zhou Peiming Mar 2022

Characteristics Of Coal Reservoirs And Favorable Areas Classification And Optimization Of Cbm Planning Blocks In Guizhou Province, Xiang Wenxin, Sang Shuxun, Wu Zhangli, Tu Bin, Guo Zhijun, Han Sijie, Zhou Xiaozhi, Zhou Peiming

Coal Geology & Exploration

The scientific evaluation of favorable CBM blocks concerns the deployment of CBM exploration and development and the maximization of benefits. On the basis of the existing geological and engineering data, the geological background, resource characteristics, occurrence characteristics and reservoir characteristics of CBM are studied in the 18 blocks with unregistered mining rights in Guizhou Province. According to the principle of coal rank classification and evaluation, the optimum block among the 18 blocks is selected by using the multi-level fuzzy comprehensive evaluation method. The results are as follows. (1) The coal seams of Longtan Formation in the 18 planning blocks of …

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Multi-Scale Prediction Of Coal Seam Fracture Development In Mg Block, Eastern Margin Of Ordos Basin, Zhu Guanghui, Li Zhongcheng, Shi Suzhen, Shi Hao, Lin Liming, Liu Yancheng, Zhang Xin Mar 2022

Multi-Scale Prediction Of Coal Seam Fracture Development In Mg Block, Eastern Margin Of Ordos Basin, Zhu Guanghui, Li Zhongcheng, Shi Suzhen, Shi Hao, Lin Liming, Liu Yancheng, Zhang Xin

Coal Geology & Exploration

Finding out the development characteristics of coal seam fractures is of great significance for coalbed methane exploitation and safe production of underground coal mines. Logging and seismic are effective means of geophysical identification of coal seam fractures. Electrical imaging, resistivity, density, sonic differential time, natural gamma, neutron porosity and array acoustic logs are used to describe the small scale fracture morphology of No.8 and No.9 coal seams of MG block in the eastern margin of Ordos Basin. The middle-scale fracture of No.8 and No.9 coal seams was predicted by prestack Azimuth AVO inversion in OVT domain. And the large-scale fracture …

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Geological Adaptability Analysis And Operational Parameter Optimization For Staged Fracturing Horizontal Wells In Coal Seam Roof, Jiang Zaibing, Li Haozhe, Xu Yaobo, Zhang Qun, Li Guihong, Fan Yao, Jiang Wenping, Shu Jiansheng, Pang Tao, Cheng Bin Mar 2022

Geological Adaptability Analysis And Operational Parameter Optimization For Staged Fracturing Horizontal Wells In Coal Seam Roof, Jiang Zaibing, Li Haozhe, Xu Yaobo, Zhang Qun, Li Guihong, Fan Yao, Jiang Wenping, Shu Jiansheng, Pang Tao, Cheng Bin

Coal Geology & Exploration

The technique of staged fracturing horizontal wells in coal seam roof is effective for efficient extraction of coalbed methane (CBM) in broken soft and low-permeability coal seams. With the help of the major national science and technology projects of the 13th Five Year Plan for National Economic and Social Development, the efficient extraction technology of CBM by staged fracturing horizontal wells in coal seam roof was studied. By using theoretical analysis and numerical simulation, the fracture propagation patterns in different in-situ stress states were compared, and the influence of the angle between the horizontal well layout orientation and the minimum …

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Production Characteristics Of Deep Coalbed Methane Gas Reservoirs In Daning-Jixian Block And Its Development Technology Countermeasures, Nie Zhihong, Shi Xiaosong, Sun Wei, Yan Xia, Huang Hongxing, Liu Ying, Feng Yanqing Mar 2022

Production Characteristics Of Deep Coalbed Methane Gas Reservoirs In Daning-Jixian Block And Its Development Technology Countermeasures, Nie Zhihong, Shi Xiaosong, Sun Wei, Yan Xia, Huang Hongxing, Liu Ying, Feng Yanqing

Coal Geology & Exploration

The Ordos Basin is rich in deep coalbed methane resources with a depth of more than 2 000 m, which is an important coalbed methane exploration and development area. A number of tests on deep coalbed methane have been carried out in Daning-Jixian Block, and preliminary results have been achieved, but the main technology of scale-efficient development needs to be studied. On the basis of the analysis of experimental data, production data and fracture monitoring data, and by the evaluation of the characteristics, production performance and fracturing effect of deep coalbed methane reservoirs in Daning-Jixian Block, the production characteristics of …

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Climate Change Could Make Allergy Season Longer, Odu Expert Says, Amber Kennedy Mar 2022

Climate Change Could Make Allergy Season Longer, Odu Expert Says, Amber Kennedy

News Items

No abstract provided.

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Odu’S Peter Bernath Participates In Study That Reveals Damage To Ozone Layer From Extreme Wildfires, Tiffany Whitfield Mar 2022

Odu’S Peter Bernath Participates In Study That Reveals Damage To Ozone Layer From Extreme Wildfires, Tiffany Whitfield

News Items

No abstract provided.

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Image Classification Based On Sparse Representation In The Quaternion Wavelet Domain, Long H. Ngo, Nikolay Metodiev Sirakov, Marie Luong, Emmanuel Viennet Mar 2022

Image Classification Based On Sparse Representation In The Quaternion Wavelet Domain, Long H. Ngo, Nikolay Metodiev Sirakov, Marie Luong, Emmanuel Viennet

Faculty Publications

In this study, we propose a novel sparse representation learning method in the Quaternion Wavelet (QW) domain for multi-class image classification. The proposed method takes advantages from: i) the QW decomposition, which promotes sparsity and provides structural information about the image data while allowing approximate shift-invariance, to extract meaningful features from low-frequency QW subbands, ii) the dimensionality reduction method using Principal Component Analysis (PCA) for reducing the complexity of the problem, and iii) the sparse representation of the generated QW features to efficiently learn and capture the meaningful and compact information of this data. After the QW decomposition, the features …

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Proposed L-Shape Pattern On Ufs Acm For Risk Analysis, Abhishek Asthana, Padma Lochan Pradhan Dr Mar 2022

Proposed L-Shape Pattern On Ufs Acm For Risk Analysis, Abhishek Asthana, Padma Lochan Pradhan Dr

Journal of Digital Forensics, Security and Law

At this cloud age, there is tremendous growth in business, services, resources, and cloud technology. This growth comes with a risk of unsafe, unordered, and uncertainty due to unauthorized access and theft of confidential propriety data. Our objective is to model around Read, Write and Execute to resolve these unordered, unsafe, and uncertain issues. We will develop a L-Shape pattern model matching UFS ACM to minimize the accessibilities based on RIGHT & ROLE of the resources and maximize the quality of services for safety and high availability. The preventive, detective, corrective (PDC) services are the major roles for all levels …

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A Combined Approach For Private Indexing Mechanism, Pranita Maruti Desai Ms., Vijay Maruti Shelake Mr. Mar 2022

A Combined Approach For Private Indexing Mechanism, Pranita Maruti Desai Ms., Vijay Maruti Shelake Mr.

Journal of Digital Forensics, Security and Law

Private indexing is a set of approaches for analyzing research data that are similar or resemble similar ones. This is used in the database to keep track of the keys and their values. The main subject of this research is private indexing in record linkage to secure the data. Because unique personal identification numbers or social security numbers are not accessible in most countries or databases, data linkage is limited to attributes such as date of birth and names to distinguish between the number of records and the real-life entities they represent. For security reasons, the encryption of these identifiers …

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How Prey Defense Patterns Predator-Prey Distributions, Evan Haskell Mar 2022

How Prey Defense Patterns Predator-Prey Distributions, Evan Haskell

Mathematics Colloquium Series

In ecology, predator and prey species share a common interest in survival. However, this common interest places these species at odds with each other. Predators need to consume prey for their survival. Prey, on the other hand, do not survive if they are consumed. To meet their needs, predators engage in foraging or prey-taxis behaviors whereby they seek areas of high prey density. For prey there are numerous defense strategies to engage including aposematic mechanisms to advertise they are not worth the predator’s while, attacking the predator through chemical or community defense mechanisms, and alarm calls to seek assistance from …

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On Efficacy And Effectiveness Of Vaccines: A Mathematical Approach Based On Conditional Probability With Applications To The Covid-19 Context, Flavius Guias Mar 2022

On Efficacy And Effectiveness Of Vaccines: A Mathematical Approach Based On Conditional Probability With Applications To The Covid-19 Context, Flavius Guias

Spora: A Journal of Biomathematics

This paper presents a mathematically formalized approach which points out the relation between efficacy and effectiveness of vaccines. The first term denotes the relative degree of protection in clinical trials or under ideal conditions, while the latter is based on observed real-life data. We define the efficacy by a similar formula to the effectiveness, but the probabilities involved in the relative risk are conditional with respect to the exposure to the virus. If exposure and vaccination status are independent, the two quantities are equal. Otherwise, the observed value of the effectiveness is a biased one, as it could be seen …

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Prime Labelings On Planar Grid Graphs, Stephen James Curran Mar 2022

Prime Labelings On Planar Grid Graphs, Stephen James Curran

Theory & Applications of Graphs

It is known that for any prime p and any integer n such that 1≤n≤p there exists a prime labeling on the pxn planar grid graph PpxPn. We show that PpxPn has a prime labeling for any odd prime p and any integer n such that that p<n≤p2.

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Characterizing Edge Betweenness-Uniform Graphs, Jana Coroničová Hurajová, Tomas Madaras, Darren A. Narayan Mar 2022

Characterizing Edge Betweenness-Uniform Graphs, Jana Coroničová Hurajová, Tomas Madaras, Darren A. Narayan

Theory & Applications of Graphs

The betweenness centrality of an edge e is, summed over all u,v ∈ V(G), the ratio of the number of shortest u,v-paths in G containing e to the number of shortest u,v-paths in G. Graphs whose vertices all have the same edge betweenness centrality are called edge betweeness-uniform. It was recently shown by Madaras, Hurajová, Newman, Miranda, Fl´orez , and Narayan that of the over 11.7 million graphs with ten vertices or fewer, only four graphs are edge betweenness-uniform but not edge-transitive. In this paper we present new results involving properties of betweenness-uniform graphs.

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Chromatic Polynomials Of Signed Book Graphs, Deepak Sehrawat, Bikash Bhattacharjya Mar 2022

Chromatic Polynomials Of Signed Book Graphs, Deepak Sehrawat, Bikash Bhattacharjya

Theory & Applications of Graphs

For m ≥ 3 and n ≥ 1, the m-cycle book graph B(m,n) consists of n copies of the cycle Cm with one common edge. In this paper, we prove that (a) the number of switching non-isomorphic signed B(m,n) is n+1, and (b) the chromatic number of a signed B(m,n) is either 2 or 3. We also obtain explicit formulas for the chromatic polynomials and the zero-free chromatic polynomials of switching non-isomorphic signed book graphs.

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Comparison Of Recent Survey Techniques For Estimating Benthic Cover On Caribbean Mesophotic Reefs, Joseph R. Pawlik, Roy A. Armstrong, Stephanie Farrington, John Reed, Sara Rivero-Calle, Hanumant Singh, Brian K. Walker, Jason White Mar 2022

Comparison Of Recent Survey Techniques For Estimating Benthic Cover On Caribbean Mesophotic Reefs, Joseph R. Pawlik, Roy A. Armstrong, Stephanie Farrington, John Reed, Sara Rivero-Calle, Hanumant Singh, Brian K. Walker, Jason White

Marine & Environmental Sciences Faculty Articles

Highly divergent estimates of benthic cover of sponges have been reported for Caribbean mesophotic reefs (90-100 m) based on quadrat point-intercept data collection using 2 methods: visual surveys conducted in situ by technical divers, and analyses of photographs taken by unmanned underwater vehicles (UUVs). The second method has been criticized for potential errors from image distortion caused by variable camera angle relative to the substratum, but without a broader comparison of both methods. We find that studies that have used the UUV-based method are advantageous for a number of reasons, most importantly: (1) access to the full mesophotic zone, (2) …

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Efficient Message Dissemination On Curve Road In Vehicular Networks, Shidong Huang, Chuanhe Huang, Dongfang Wu, Yabo Yin, M. Wasim Abbas Ashraf, Bin Fu Mar 2022

Efficient Message Dissemination On Curve Road In Vehicular Networks, Shidong Huang, Chuanhe Huang, Dongfang Wu, Yabo Yin, M. Wasim Abbas Ashraf, Bin Fu

Computer Science Faculty Publications

Effective emergency message dissemination is a great importance on a specific road in vehicular networks (VN). The existing methods are not most efficient solutions for message dissemination on the curve road, which primarily focus on highway and urban road. In order to improve the efficiency of message dissemination on the curved road, the paper proposed a message dissemination method based on bidirectional relay nodes. The message can be disseminated in two directions simultaneously. The paper designed a relay node selection method based on the neighbor nodes’ coverage length of the road. Different waiting delays are assigned to the neighbor nodes …

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