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Death line for radio pulsars in braneworlds 星际中射电脉冲星的死亡线
Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences Pub Date : 2020-04-08 DOI: 10.56017/2181-1318.1058
Djavlanbek Rayimbaev, S. Palvanov, M. Umaraliyev, Malika Khudoyberdiyeva
{"title":"Death line for radio pulsars in braneworlds","authors":"Djavlanbek Rayimbaev, S. Palvanov, M. Umaraliyev, Malika Khudoyberdiyeva","doi":"10.56017/2181-1318.1058","DOIUrl":"https://doi.org/10.56017/2181-1318.1058","url":null,"abstract":"We investigate the effects of braneworlds on energetic processes in plasma magnetosphere of neutron stars. Obtained that the presence of brane charge causes an increase in the size of the polar cap region. It has shown that the polar capsize of neutron stars with larger rotation period and compactness parameter is also larger. We have studied deathline of radio pulsar in braneworld. Obtained that the deathline shifted down and the pulsars which lying on the deathline become visible in radio band. Moreover, we have extended particle acceleration in polar cap of neutron stars in the presence of the brane charge, obtain that in both curvature radiation (γ ∼ 106) and inverse Compton scattering (50 . γ . 104) cases the acceleration \"rate\" of the accelerating charged particle is significantly smaller in the presence of the brane charge.","PeriodicalId":127023,"journal":{"name":"Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131318626","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
Change in the physical and chemical properties of oil-contaminated soil in the steppe zone 草原带石油污染土壤理化性质的变化
Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences Pub Date : 2020-04-08 DOI: 10.56017/2181-1318.1055
Z. Jabbarov, Tokhtasin Abdrakhmanov, S. Akhmedov, Urol Nomozov, Muqaddas Abdurahmonova
{"title":"Change in the physical and chemical properties of oil-contaminated soil in the steppe zone","authors":"Z. Jabbarov, Tokhtasin Abdrakhmanov, S. Akhmedov, Urol Nomozov, Muqaddas Abdurahmonova","doi":"10.56017/2181-1318.1055","DOIUrl":"https://doi.org/10.56017/2181-1318.1055","url":null,"abstract":"Today, around the world as a result of the activities of industrial enterprises, mining, their use, as well as other anthropogenic factors, there is a chemical pollution of the soil cover, a change in soil properties and fertility. Pollution of soils of various types leads to the formation of problems such as soil degradation, a decrease in the qualitative and quantitative level of fertility, as well as other problems associated with the ecosystem. Today, the urgent task is to create remediation measures for soils contaminated to varying degrees with oil and oil products, corresponding to the climatic conditions of the territory. Actual problems are studying the state of pollution by sources, for reclamation of soils contaminated with oil and oil products in the desert zone, their difference, determining the physicochemical, agrochemical, microbiological, biological properties of soils, separation of factors, algorithms, stages of restoration, the choice of measures taking into account the properties of soils and the nature of pollution, periods of reclamation processes, development of primary indicators and factors of soil fertility restoration, analysis of the temporary state of contaminated soils, the creation of cartograms for predicting the future state of soil pollution, the appointment of measures for the rational use of land resources based on the data obtained.","PeriodicalId":127023,"journal":{"name":"Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127921064","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 negative eigenvalues of the discrete Schrödinger operator with non-local potential 具有非局部势的离散Schrödinger算子的负特征值
Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences Pub Date : 2020-04-08 DOI: 10.56017/2181-1318.1052
Z. Muminov, Sh. S. Lakaev
{"title":"On negative eigenvalues of the discrete Schrödinger operator with non-local potential","authors":"Z. Muminov, Sh. S. Lakaev","doi":"10.56017/2181-1318.1052","DOIUrl":"https://doi.org/10.56017/2181-1318.1052","url":null,"abstract":"On the d-dimensional lattice Zd, d = 1, 2 the discrete Schrödinger operator Hλμ with non-local potential constructed via the Dirac delta function and shift operator is considered. The dependency of negative eigenvalues of the operator on the parameters is explicitly derived.","PeriodicalId":127023,"journal":{"name":"Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122349226","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: 2
On the asymptotic behavior of branching processes with stationary immigration 具有平稳迁移的分支过程的渐近行为
Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences Pub Date : 2020-04-08 DOI: 10.56017/2181-1318.1054
Y. Khusanbaev, S. Sharipov
{"title":"On the asymptotic behavior of branching processes with stationary immigration","authors":"Y. Khusanbaev, S. Sharipov","doi":"10.56017/2181-1318.1054","DOIUrl":"https://doi.org/10.56017/2181-1318.1054","url":null,"abstract":"In this paper, we consider nearly critical branching processes with immigration. We study the convergence of a sequence of nearly critical branching processes with immigration when immigration is a stationary in wide sense. Moreover, we derive an asymptotic for characteristic function of this process.","PeriodicalId":127023,"journal":{"name":"Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121577498","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: 2
Fixing mobile desert sands: definition of water resistance, mechanical strength and mechanism of fixing 流动沙漠沙的固定:抗水性能的定义、机械强度及固定机理
Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences Pub Date : 2020-04-08 DOI: 10.56017/2181-1318.1057
S. Kuldasheva, I. Ahmadjonov, N. Adizova, I. Eshmetov, K. Akbarov
{"title":"Fixing mobile desert sands: definition of water resistance, mechanical strength and mechanism of fixing","authors":"S. Kuldasheva, I. Ahmadjonov, N. Adizova, I. Eshmetov, K. Akbarov","doi":"10.56017/2181-1318.1057","DOIUrl":"https://doi.org/10.56017/2181-1318.1057","url":null,"abstract":"The possibility of the formation of a water-resistant structures in dispersions of saline soils by using a composition of additives combining a surfactant and a fixing agent, generally providing the effect of dispersed hardening, is considered. The data by investigation of method of fixing the sands of the Surkhandarya region with complex additives obtained on the basis of the waste of the Kungrad soda plant are presented. It is shown that the basis of the proposed method of fixing saline soils with complex additives is the process of converting their surface layers (up to 5 cm) from free-dispersed state to coherent-dispersed state by forming a structures (crust) consisting of water-resistant macroaggregates > 1.0 mm with mechanical strength up to 3.0MPa.","PeriodicalId":127023,"journal":{"name":"Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122772963","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: 4
Choosing the structure of convolutional neural networks for face recognition 选择卷积神经网络的结构用于人脸识别
Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences Pub Date : 2020-04-08 DOI: 10.56017/2181-1318.1050
K. Khudaybergenov
{"title":"Choosing the structure of convolutional neural networks for face recognition","authors":"K. Khudaybergenov","doi":"10.56017/2181-1318.1050","DOIUrl":"https://doi.org/10.56017/2181-1318.1050","url":null,"abstract":"Evaluating the number of hidden neurons and hidden layers necessary for solving of face recognition, pattern recognition and classi cation tasks is one of the key problems in arti cial neural networks. In this note, we show that arti cial neural network with a two hidden layer feed forward neural network with d inputs, d neurons in the rst hidden layer, 2d+2 neurons in the second hidden layer, k outputs and with a sigmoidal in nitely di erentiable function can solve face recognition tasks. This result can be applied to design pattern recognition and classi cation models with optimal structure in the number of hidden neurons and hidden layers. In addition, we propose a new type of convolutional neural network, which is capable to extract most powerful features. The experimental results over well-known benchmark datasets shows that the convergence and the accuracy of the proposed model of arti cial neural network is acceptable. Findings in this paper are experimentally analyzed on ve di erent face datasets from machine learning repository.","PeriodicalId":127023,"journal":{"name":"Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129151291","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 number of the discrete spectrum of two-particle discrete Schröodinger operators 关于两粒子离散Schröodinger算子的离散谱数
Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences Pub Date : 2020-04-08 DOI: 10.56017/2181-1318.1051
Z. Muminov, Utkir Kuljanov, S. Alladustov
{"title":"On the number of the discrete spectrum of two-particle discrete Schröodinger operators","authors":"Z. Muminov, Utkir Kuljanov, S. Alladustov","doi":"10.56017/2181-1318.1051","DOIUrl":"https://doi.org/10.56017/2181-1318.1051","url":null,"abstract":"We consider a family of discrete Schrödinger operators hd(k), where k is the two-particle quasi-momentum varying in Td = (−π, π]d, associated to a system of two-particles on the d dimensional lattice Zd, d ≥ 1. The CwikelLieb-Rozenblum (CLR)-type estimates are written for hd(k) when the Fermi surface E−1 k (em(k)) of the associated dispersion relation is a one point set at em(k), the bottom of the essential spectrum. Moreover, when the Fermi surface E−1 k (em(k)) is of dimension d−1 or d−2, we obtain the necessary and su cient conditions for the existence of in nite discrete spectrum of hd(k), while in the case dimE−1 k (em(k)) ≤ d− 3, the discrete spectrum of h d(k) is nite.","PeriodicalId":127023,"journal":{"name":"Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127779016","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: 2
Jump theorems for the Bochner-Martinelli integral in domains with a piecewise smooth boundary 分段光滑边界域上Bochner-Martinelli积分的跳跃定理
Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences Pub Date : 2020-02-24 DOI: 10.56017/2181-1318.1048
A. Kytmanov, D. Dzhumabaev, B. Utemuratov, B. Prenov
{"title":"Jump theorems for the Bochner-Martinelli integral in domains with a piecewise smooth boundary","authors":"A. Kytmanov, D. Dzhumabaev, B. Utemuratov, B. Prenov","doi":"10.56017/2181-1318.1048","DOIUrl":"https://doi.org/10.56017/2181-1318.1048","url":null,"abstract":"","PeriodicalId":127023,"journal":{"name":"Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115826734","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
The effect of prebiotics on intestinal digestion of carbohydrates in lead intoxicated rats 益生元对铅中毒大鼠肠道碳水化合物消化的影响
Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences Pub Date : 2019-12-24 DOI: 10.56017/2181-1318.1047
L. S. Kuchkarova, Irodakhon I. Karimova, Gulchekhra T. Kudeshova, K. Kayumov
{"title":"The effect of prebiotics on intestinal digestion of carbohydrates in lead intoxicated rats","authors":"L. S. Kuchkarova, Irodakhon I. Karimova, Gulchekhra T. Kudeshova, K. Kayumov","doi":"10.56017/2181-1318.1047","DOIUrl":"https://doi.org/10.56017/2181-1318.1047","url":null,"abstract":"It has been shown the lead intoxication of growing rats result in increase the cavity and membrane carbohydrate hydrolysis and glucose absorption from small intestine which leads to hyperglicemiya. The oral treatment of intoxicated rats with inulin or lactulose results in decrease of carbohydrate assimilation in small intestine and content glucose level in blood. The correcting effect of lactulose on normalization of carbohydrate assimilation is more expressed in compare with inulin. So, inulin and/or lactulose take part in improving of adaptation of the carbohydrate assimilation system in the small intestine during intoxication with lead ions in growing rats. This suggests the prospect of their use as physiologically acceptable additives to stabilize carbohydrate digestion and blood glucose levels in lead and, possibly, other heavy metal intoxication in the growing organism.","PeriodicalId":127023,"journal":{"name":"Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114026494","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
A theoretical study an influence of oxygen group elements to rotational barrier of 2-(2'-pyridyl)-1,3,4-oxa(thia, selena and tellura) diazoles 理论研究了氧基元素对2-(2′-吡啶基)-1,3,4-氧(辛酸、硒酸和碲酸)重唑旋转势垒的影响
Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences Pub Date : 2019-12-18 DOI: 10.56017/2181-1318.1044
A. Eshimbetov, Khamza Toshov, I. Kaur, Alisher Khaitboev
{"title":"A theoretical study an influence of oxygen group elements to rotational barrier of 2-(2'-pyridyl)-1,3,4-oxa(thia, selena and tellura) diazoles","authors":"A. Eshimbetov, Khamza Toshov, I. Kaur, Alisher Khaitboev","doi":"10.56017/2181-1318.1044","DOIUrl":"https://doi.org/10.56017/2181-1318.1044","url":null,"abstract":"Surveying of the refernces shows that selenium and tellurium containing compounds will be one of the most promising heterocycles in the future. Therefore, the influence of oxygen group elements – O, S, Se and Te to rotational barrier heights of 2-(2’-pyridyl)-1,3,4-oxa (thia, selena and tellura) diazoles were investigated by DFT/def2-TZVP method and also by DFT/6-311G(d) method only for O, S and Se series. And also, their thermodynamic parameters (∆H,∆G) were calculated in gas phase. Furthermore, some model compounds with conjugated C=C-C=C, N=C-C=C and N=C-C=N fragments with neighbouring chalcogen atoms were considered. It was found that, a rising of barrier heights in the case of 2-(2’-pyridyl)-1,3,4-oxa(thia, selena and tellura)diazoles and also, in the model compounds with N=C-C=N fragment by increasing atomic number of chalcogen atom. By going from O to Te the rising of HOMO level and decreasing of HOMO-LUMO energetic gap were observed. It was found that, turning of pyridyl ring to ±30◦ from the coplanar cis (cyn) structure due to the lone pair electron repulsion of nitrogen atoms of N=C-C=N fragment in the case of S, Se and Te containing considered compounds. This is also leads to stability of the trans (anti) structure relatively to cis (cyn) structure and the trans-cis energy difference is increasing by going O to Te. And also, the trans structure is becoming more stable due to the hydrogen bond between nitrogen atom of chalcogenazole ring and H atom of pyridine ring in orto position.","PeriodicalId":127023,"journal":{"name":"Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130648745","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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