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Gauge Symmetries in Physical Fields (Review) 物理领域的规范对称性(综述)
Global Journal of Science Frontier Research Pub Date : 2021-12-06 DOI: 10.34257/gjsfravol21is4pg1
T. Kambe
{"title":"Gauge Symmetries in Physical Fields (Review)","authors":"T. Kambe","doi":"10.34257/gjsfravol21is4pg1","DOIUrl":"https://doi.org/10.34257/gjsfravol21is4pg1","url":null,"abstract":"Gauge invariance is one of the fundamental symmetries in theoretical physics. In this paper, the gauge symmetry is reviewed to see how it is working in fundamental physical fields: Electromagnetism, Quantum Electro Dynamics and Geometric Theory of Gravity. In the 19th century, the gauge invariance was recognized as a mathematical non-uniqueness of the electromagnetic potentials. Real recognition of the gauge symmetry and its physical significance required two new fields developed in the 20th century: the relativity theory for physics of the world structure of linked 4d-spacetime and the quantum mechanics for the new dimension of a phase factor in complex representation of wave function. Finally the gauge theory was formulated on the basis of the gauge principle which played a role of guiding principle in the study of physicalfields such as Quantum Electrodynamics, Particle Physics and Theory of Gravitation. Fluid mechanics of a perfect fluid can join in this circles, which is another motivation of the present review. There is a hint of fluid gauge theory in the general representation of rotational flows of an ideal compressible fluid satisfying the Euler’s equation, found in 2013 by the author. In fact, law of mass conservation can be deduced from the gauge symmetry equipped in the new system of fluid-flow field combined with a gauge field, rather than given a priori.","PeriodicalId":12547,"journal":{"name":"Global Journal of Science Frontier Research","volume":"54 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80006445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Composition, Density and Spatial Distribution of Zooplankton in Inner Ambon Bay, Indonesia 印度尼西亚安汶湾内浮游动物的组成、密度和空间分布
Global Journal of Science Frontier Research Pub Date : 2021-11-25 DOI: 10.34257/gjsfrcvol21is5pg7
J. Latumeten, F. Pello, V. D. V. Latumeten
{"title":"Composition, Density and Spatial Distribution of Zooplankton in Inner Ambon Bay, Indonesia","authors":"J. Latumeten, F. Pello, V. D. V. Latumeten","doi":"10.34257/gjsfrcvol21is5pg7","DOIUrl":"https://doi.org/10.34257/gjsfrcvol21is5pg7","url":null,"abstract":"Inner Ambon Bay is part of Ambon Bay; it is semi-closed area and a small pelagic fish fishing ground, especially anchovy. The anchovy is a zooplankton predator; therefore the existence of anchovy is affected by the abundance of zooplankton. The aims of the research are to obtain information on the composition, density, and spatial distribution of the zooplankton in these waters. Data of zooplankton composition were obtained from sampling by using plankton net at ten observation stations. Meanwhile, data of densities were collected using a scientific hydroacoustic system, BioSonic DTX supported with split-beam technology, on six parallel transect lines and one cross-parallel transect line. Geostatistical analyses technique was used to describe horizontal distributions of zooplankton, and vertical distributions pattern were plot in the graphs. The result shows that the zooplankton community is dominated by Copepod and meroplankton. The highest average density was found in August (9393 ind./m2),while the lowest density was in June (903 ind./m2).","PeriodicalId":12547,"journal":{"name":"Global Journal of Science Frontier Research","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82462687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Competitiveness Analysis of the Acai Berry Producers of Northeastern of Para 帕拉州东北部巴西莓生产商竞争力分析
Global Journal of Science Frontier Research Pub Date : 2021-11-17 DOI: 10.34257/gjsfrdvol21is6pg1
Dinaldo do Nascimento Araujo, Marcelo de Souza Correia, Alexandre Jorge Gaia Cardoso
{"title":"Competitiveness Analysis of the Acai Berry Producers of Northeastern of Para","authors":"Dinaldo do Nascimento Araujo, Marcelo de Souza Correia, Alexandre Jorge Gaia Cardoso","doi":"10.34257/gjsfrdvol21is6pg1","DOIUrl":"https://doi.org/10.34257/gjsfrdvol21is6pg1","url":null,"abstract":"The purpose of this study is to identify what the perspectives of competitiveness by rural production of acai are, from terra firme and várzea in northeast Pará. Region considered the one that produces the most acai in Brazil. The main objective is to describe a certain sample of producers and to identify and evaluate the competitiveness perspectives of this sample in relation to the competitiveness factors defined in the research, starting from the null hypothesis that there are no significant differences in perspectives between terra firme and várzea producers. The theoretical basis considered for the research is composed of an approach on agrichain and factors of competitiveness. The method used for the execution of the research was the Rapid Appraisal, where a semi-structured questionnaire was prepared for the agents of the acai production chain. The main key agents taken into consideration and characterized were: Producers of acai; intermediaries and representatives of some organizations.","PeriodicalId":12547,"journal":{"name":"Global Journal of Science Frontier Research","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74825529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Null Distribution of the Test Statistic for Model Selection via Marginal Screening: Implications for Multivariate Regression Analysis 边际筛选模型选择检验统计量的零分布:多元回归分析的意义
Global Journal of Science Frontier Research Pub Date : 2021-10-21 DOI: 10.34257/gjsfrgvol21is1pg23
A. V. Rubanovich, V. Saenko
{"title":"Null Distribution of the Test Statistic for Model Selection via Marginal Screening: Implications for Multivariate Regression Analysis","authors":"A. V. Rubanovich, V. Saenko","doi":"10.34257/gjsfrgvol21is1pg23","DOIUrl":"https://doi.org/10.34257/gjsfrgvol21is1pg23","url":null,"abstract":"Marginal screening (MS) is the computationally simple and commonly used for the dimension reduction procedures. In it, a linear model is constructed for several top predictors, chosen according to the absolute value of marginal correlations with the dependent variable. Importantly, when kpredictors out of mprimary covariates are selected, the standard regression analysis may yield false-positive results if m>> k(Freedman's paradox). In this work, we provide analytical expressions describing null distribution of the test statistics for model selection via MS. Using the theory of order statistics, we show that under MS, the common F-statistic is distributed as a mean of ktop variables out of mindependent random variables having a 21χdistribution. Based on this finding, we estimated critical p-values for multiple regression models after MS, comparisons with which of those obtained in real studies will help researchers to avoid false-positive result. Analytical solutions obtained in the work are implemented in a free Excel spreadsheet program.","PeriodicalId":12547,"journal":{"name":"Global Journal of Science Frontier Research","volume":"138 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76616178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Isolation, Selection and Antimicrobial Activity of Actinomycetes from Mangrove Soil of Can Gio Forest, Hochiminh City, Vietnam 越南胡志明市芹焦红树林土壤中放线菌的分离、选择及抑菌活性研究
Global Journal of Science Frontier Research Pub Date : 2021-10-04 DOI: 10.34257/gjsfrcvol21is4pg7
N. Hai, C. N. Diệp
{"title":"Isolation, Selection and Antimicrobial Activity of Actinomycetes from Mangrove Soil of Can Gio Forest, Hochiminh City, Vietnam","authors":"N. Hai, C. N. Diệp","doi":"10.34257/gjsfrcvol21is4pg7","DOIUrl":"https://doi.org/10.34257/gjsfrcvol21is4pg7","url":null,"abstract":"The Can Gio Mangrove is a Biosphere Reserve of UNESCO since 2000 and it is also a well-known example of “mangrove afforestation and reforestation area’’. A total of 63 actinomycetes were isolated from 25 samples of 9 different sites in mangrove forest soil Can Gio, HoChiMinh city, Vietnam. Almost their colonies have round-shaped; milky, white clear and yellow, entire or loabate margin; diameter size of these colonies varied from 0.2 to 3.0 mm. Twenty-nine of 63 tested isolates could produce antimicrobial active metabolites inhibiting at least one of the tested pathogens and 9 isolates were selected for 16S rDNA sequencing. The result showed that genus Streptomyces (8 isolates) and other genera including 1 isolates were Gram-negative bacteria (Stenotrophomonas). The antimicrobial activity and the amplifying genes coding for polyketide synthetase (PKS) and nonribosomal peptide synthetase (NRPS) showed that 8 strains had broad-spectrum antimicrobial activity, mainly against gram-positive bacteria as Bacillus cereus and Staphylococcus aureus.","PeriodicalId":12547,"journal":{"name":"Global Journal of Science Frontier Research","volume":"23 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90710411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
From Majorana Neutrino and Dark Neutrino 0 to Dark Spin Particles 从马约拉纳中微子和暗中微子0到暗自旋粒子
Global Journal of Science Frontier Research Pub Date : 2021-09-22 DOI: 10.34257/gjsfravol21is3pg17
Shaoxu Ren
{"title":"From Majorana Neutrino and Dark Neutrino 0 to Dark Spin Particles","authors":"Shaoxu Ren","doi":"10.34257/gjsfravol21is3pg17","DOIUrl":"https://doi.org/10.34257/gjsfravol21is3pg17","url":null,"abstract":"In current theory of particle physics, the values of Casimir Operator, that is abbreviated to CO, of spin angular momentum for elementary particles are thought to be greater than zero.","PeriodicalId":12547,"journal":{"name":"Global Journal of Science Frontier Research","volume":"168 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72701527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
On the Dependence of the Fill Factor of the Solar Module on the Temperature 太阳能组件填充系数对温度的依赖性研究
Global Journal of Science Frontier Research Pub Date : 2021-09-22 DOI: 10.34257/gjsfravol21is3pg1
A. Kanareykin
{"title":"On the Dependence of the Fill Factor of the Solar Module on the Temperature","authors":"A. Kanareykin","doi":"10.34257/gjsfravol21is3pg1","DOIUrl":"https://doi.org/10.34257/gjsfravol21is3pg1","url":null,"abstract":"The work is devoted to the conversion and use of solar energy in solar panels. The article shows that one of the clue parameters for evaluating the efficiency of solar panels and photovoltaic cells, the fill factor decreases with increasing temperature. The issue of reducing the influence of the temperature factor on the efficiency of solar panels is also considered. Based on the research, the conclusion is given that the idling voltage should be as high as possible.","PeriodicalId":12547,"journal":{"name":"Global Journal of Science Frontier Research","volume":"100 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85801428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Nanostructures of 2d Transition Metal Dichalcogenides for Hydrogen Generation underAlkaline Conditions: From Theoretical Models to Practical Electrocatalysts 二维过渡金属二硫族化合物在碱性条件下产氢的纳米结构:从理论模型到实际电催化剂
Global Journal of Science Frontier Research Pub Date : 2021-09-04 DOI: 10.34257/ljrsvol21is3pg25
Zhexu Xi
{"title":"Nanostructures of 2d Transition Metal Dichalcogenides for Hydrogen Generation under\u0000Alkaline Conditions: From Theoretical Models to Practical Electrocatalysts","authors":"Zhexu Xi","doi":"10.34257/ljrsvol21is3pg25","DOIUrl":"https://doi.org/10.34257/ljrsvol21is3pg25","url":null,"abstract":"Hydrogen has been considered as the cleanest renewable energy and the ideal alternative to fossil fuels. Electrocatalytic Hydrogen Evolution Reaction (HER) via water splitting also plays an indispensable role in high-efficiency energy con- version. Compared with the well-investigated acidic HER, the relatively slow kinetics and unclear mechanism of HER in alkaline environments largely make the design of electrocatalysts a trial-and-error process, retarding the scalable development of efficient, sustainable hydrogen production. Furthermore, two-dimensional transition metal dichalcogenides (2D TMDs) have been demonstrated to be promising acidic/ alkaline HER catalysts in water electrolysis due to their outstanding atom-level thickness and surface-based properties.","PeriodicalId":12547,"journal":{"name":"Global Journal of Science Frontier Research","volume":"53 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86697092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Synthesis, Crystal Structure, Hirshfeld Surface, Energy Framework and Molecular Docking of 2-(((6-Methoxy pyridin-3-yl)imino)methyl)Phenol 2-(((6-甲氧基吡啶-3-基)亚氨基)甲基)苯酚的合成、晶体结构、Hirshfeld表面、能量框架和分子对接
Global Journal of Science Frontier Research Pub Date : 2021-09-03 DOI: 10.34257/gjsfrbvol21is2pg9
M. Singh, S. Anthal, P. Akhileshwari, M. A. Sridhar, H. M. Vinusha, S. Bindya, M. Begum, R. Chandrasekaran, M. Saminathan, R. Kant
{"title":"Synthesis, Crystal Structure, Hirshfeld Surface, Energy Framework and Molecular Docking of 2-(((6-Methoxy pyridin-3-yl)imino)methyl)Phenol","authors":"M. Singh, S. Anthal, P. Akhileshwari, M. A. Sridhar, H. M. Vinusha, S. Bindya, M. Begum, R. Chandrasekaran, M. Saminathan, R. Kant","doi":"10.34257/gjsfrbvol21is2pg9","DOIUrl":"https://doi.org/10.34257/gjsfrbvol21is2pg9","url":null,"abstract":"The structure of 2-(((6-methoxypyridin-3-yl)imino)methyl)phenol (MPIMP) (C13H12N2O2) has been determined by X-ray diffraction methods. It crystallizes in the tetragonal crystal system with space group P42/n and unit cell dimensions a = 14.2958(3) Å, b = 14.2958(3) Å, c = 11.0179(3) Å, V = 2251.73(12) Å3, Z = 8. The structure has been refined by full-matrix least square procedure to a final R-value of 0.0518(wR2= 0.1312) for 1709 observed reflections. The molecules linked via two intermolecular (C-H...N and C-H...O) hydrogen bonds. The crystal structure was further stabilized by a strong intramolecular N-H...O hydrogen bond. The Hirshfeld surface analysis reveals the interaction contacts of the molecule and the strength of molecular packing in the crystal. The energy framework has been performed through different intermolecular interaction energies for structural stability. The molecular docking of MPIMP was performed against tuberculosis enzyme Decaprenyl-phosphoryl-b-Dribose 20-epimerase (DprE1, PDB code: 4KW5) to reconnoiter the binding interactions at the active sites.","PeriodicalId":12547,"journal":{"name":"Global Journal of Science Frontier Research","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88002336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Genetic Variation and Heritability for Juice Quality and Yield Traits in Selection of Sugarcane Genotypes under Irrigation at Early Stage in Ferké 2 Sugar Estate of Northern Ivory Coast 科特迪瓦北部ferk<s:1> 2糖业庄园早期灌溉条件下甘蔗基因型选择中汁品质和产量性状的遗传变异和遗传力
Global Journal of Science Frontier Research Pub Date : 2021-08-07 DOI: 10.34257/gjsfrdvol21is5pg7
C. Péné, Y. Béhou, Marcel Silué
{"title":"Genetic Variation and Heritability for Juice Quality and Yield Traits in Selection of Sugarcane Genotypes under Irrigation at Early Stage in Ferké 2 Sugar Estate of Northern Ivory Coast","authors":"C. Péné, Y. Béhou, Marcel Silué","doi":"10.34257/gjsfrdvol21is5pg7","DOIUrl":"https://doi.org/10.34257/gjsfrdvol21is5pg7","url":null,"abstract":"Genetic relationships between important attributes in studying sugarcane populations through breeding and direct selection, are crucialto understand how changes made by selecting one character may cause changes in others. The study aimed to determine the best yielding sugarcane genotypes tested at early selection stage under sprinkler irrigation, in comparison with a check variety (R579). The experiment was designed following a randomized complete block (RCB), with 30 cane genotypes in three replications. Each plot consisted of five dual rows of ten meters, with 0.5 and 1.90 m of inter-row spacing, i.e. 95 m² per plot and nearly 6,000 m² for the whole experiment. It was carried out on a commercial sugarcane plantation of Ferké 2, in northern Ivory Coast, over two seasons (plant cane and first ratoon) as an early-season crop from, November 29, 2018 to October 26, 2020. In each micro-plot, different agro-morphological traits were collected at harvest from three central dual rows.","PeriodicalId":12547,"journal":{"name":"Global Journal of Science Frontier Research","volume":"156 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76846232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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