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Total Fragmentation Cross Section of 158A GeV Lead Projectiles in Cu Target 被引量:1
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作者 Mukhtar Ahmed Rana Shahid Manzoor 《Chinese Physics Letters》 SCIE CAS CSCD 2008年第9期3208-3211,共4页
Total fragmentation cross section for the reaction 158A Pb ions + Cu target is measured using the most sensitive track detector CR-39. Measured values are compared with calculations. Exposures of target-detector stac... Total fragmentation cross section for the reaction 158A Pb ions + Cu target is measured using the most sensitive track detector CR-39. Measured values are compared with calculations. Exposures of target-detector stack with 158A P5 projectiles are made at CERN-SPS beam facility. Results of calibration of CR-39 detector in a charge region (63 ≤ Z ≤ 83) are also reported, which can be used for high energy particle identification using CR-39 and in determination of partial charge changing cross sections. The charge resolution δz achieved by this technique is about 0.2e. A systematic dependence of total fragmentation cross section on target properties is revealed and the corresponding results are presented. 展开更多
关键词 the power-law exponents precipitation durative abrupt precipitation change
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Radionuclide concentrations in sand samples from riverbanks of Muzaffarabad,Azad Kashmir 被引量:1
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作者 Abdul Razzaq Khan Muhammad Rafique +4 位作者 Abdul Jabbar Saeed Ur Rahman Muhammad Ikram Shahzad Muhammad Ejaiz Khan Mulaika Yasin 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第7期103-115,共13页
This paper presents the results of a radiological risk assessment arising from the presence of naturally occurring radionuclides in sand samples from three riverbanks in Muzaffarabad.The mean values obtained for 232 T... This paper presents the results of a radiological risk assessment arising from the presence of naturally occurring radionuclides in sand samples from three riverbanks in Muzaffarabad.The mean values obtained for 232 Th,226 Ra,and 40 K were found to be 44.58 ± 3.34,48.25 ± 1.77,and 239.92 ± 22.73 Bq kg^(-1),respectively.To assess the uniformity of exposure,the radium equivalent activity(Raeq) was calculated and was found to be130.47 ± 8.29 Bqkg^(-1).The current reported value for Raeqis lower than the maximum permissible value,that is,370 Bq kg^(-1),and equivalent to a gamma dose of1.5 m Svy^(-1).To investigate the possible contribution to health risks of alpha particle exposure,the radon exhalation rate(RER) from the sand samples was determined.The mean RER for all the samples was found to be335 m Bq m-^(2) h^(-1).About 43% of the samples were found to have an indoor excess lifetime cancer risk value slightly higher than recommended safety limit of 1,as proposed by the ICRP.A normalized parameter,the equivalent multiplicative factor,was defined and used to compare the current results with the findings of studies performed in other countries.Our findings are relevant to both human health and future environmental radiation monitoring. 展开更多
关键词 放射性核种 样品 克什米尔 河岸 风险评价 调查结果 226RA GAMMA
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Etchability of Latent Fission Fragment Tracks in CR-39
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作者 Mukhtar Ahmed Rana 《Chinese Physics Letters》 SCIE CAS CSCD 2007年第11期3107-3110,共4页
We report the chemical etching behaviour of the CR-39 polymer detector exposed to fission fragments of 252Cf describing etchability of latent tracks, which are like nanocylinders. The fission fragment exposed detector... We report the chemical etching behaviour of the CR-39 polymer detector exposed to fission fragments of 252Cf describing etchability of latent tracks, which are like nanocylinders. The fission fragment exposed detectors were etched in 1-7 N NaOH water solutions at temperatures 50-80℃ for 45 min in the case of track length and 180 min in the case of track diameter measurements. The reduced etch rate S (called here etchability) is determined using experimental results for all etching conditions and the etching conditions with the highest reduced etch are obtained. Physics and energetics of bulk and track etching are discussed. Possible effects causing spurious changes in determination of activation energy of etching are investigated. 展开更多
关键词 coated conductor buffer layer self-epitaxy CEO2
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A compound spike model for formation of nuclear tracks in solids
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作者 Mukhtar Ahmed RANA 《Nuclear Science and Techniques》 SCIE CAS CSCD 2007年第6期349-353,共5页
Formation of nuclear tracks in solids has been described as a thermal spike as well as a Coulomb explo- sion spike.Here,formation of nuclear tracks is described as a compound spike including partial roles of both ther... Formation of nuclear tracks in solids has been described as a thermal spike as well as a Coulomb explo- sion spike.Here,formation of nuclear tracks is described as a compound spike including partial roles of both thermal and Coulomb explosion spikes in track formation.Fractional roles of both spikes depend on atomic and electronic structure of a track detector and deposited energy density in the track detector by the incident charged particle.Be- havior of the cylindrical zone along the path of the incident particle is described mathematically in terms of bulk and individual atomic flow or movement.Defect structure of the latent nuclear tracks is described and conditions of con- tinuity and discontinuity of latent tracks are evaluated and discussed.This paper includes mathematical description, analysis and evaluation of the nuclear track formation issue in the light of published experimental and theoretical re- sults,which are useful for users of nuclear track detection technique and researchers involved in ion beam induced materials modification and ions implantation in semiconductors. 展开更多
关键词 核子轨道探测技术 晶体 固态径迹探测 探测方法
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First immunohistochemical evidence of human tendon repair following stem cell injection: A case report and review of literature
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作者 Eckhard Alt Ralf Rothoerl +4 位作者 Matthias Hoppert Hans-Georg Frank Tobias Wuerfel Christopher Alt Christoph Schmitz 《World Journal of Stem Cells》 SCIE 2021年第7期944-970,共27页
BACKGROUND Current clinical treatment options for symptomatic,partial-thickness rotator cuff tear(sPTRCT)offer only limited potential for true tissue healing and improvement of clinical results.In animal models,inject... BACKGROUND Current clinical treatment options for symptomatic,partial-thickness rotator cuff tear(sPTRCT)offer only limited potential for true tissue healing and improvement of clinical results.In animal models,injections of adult stem cells isolated from adipose tissue into tendon injuries evidenced histological regeneration of tendon tissue.However,it is unclear whether such beneficial effects could also be observed in a human tendon treated with fresh,uncultured,autologous,adipose derived regenerative cells(UA-ADRCs).A specific challenge in this regard is that UA-ADRCs cannot be labeled and,thus,not unequivocally identified in the host tissue.Therefore,histological regeneration of injured human tendons after injection of UA-ADRCs must be assessed using comprehensive,immunohistochemical and microscopic analysis of biopsies taken from the treated tendon a few weeks after injection of UA-ADRCs.CASE SUMMARY A 66-year-old patient suffered from sPTRCT affecting the right supraspinatus and infraspinatus tendon,caused by a bicycle accident.On day 18 post injury[day 16 post magnetic resonance imaging(MRI)examination]approximately 100 g of abdominal adipose tissue was harvested by liposuction,from which approximately 75×10^(6) UA-ADRCs were isolated within 2 h.Then,UA-ADRCs were injected(controlled by biplanar X-ray imaging)adjacent to the injured supraspinatus tendon immediately after isolation.Despite fast clinical recovery,a follow-up MRI examination 2.5 mo post treatment indicated the need for open revision of the injured infraspinatus tendon,which had not been treated with UAADRCs.During this operation,a biopsy was taken from the supraspinatus tendon at the position of the injury.A comprehensive,immunohistochemical and microscopic analysis of the biopsy(comprising 13 antibodies)was indicative of newly formed tendon tissue.CONCLUSION Injection of UA-ADRCs can result in regeneration of injured human tendons by formation of new tendon tissue. 展开更多
关键词 Stem cells Partial-thickness rotator cuff tear Tendon regeneration Adipose derived regenerative cells Cell-based therapy at point of care Case report
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Innovative Development and Commercialization of Technologies: Experience of Technopark "Novosibirsk"
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作者 Yury I. Shokin Boris Y. Grishnyakov Leonid K. Bobrov 《Chinese Business Review》 2012年第10期855-863,共9页
This article is concerned with analyzes of experience of Technopark "Novosibirsk" as an important part of the innovation infrastructure of the Novosibirsk region. In this article the authors are formulated prioritie... This article is concerned with analyzes of experience of Technopark "Novosibirsk" as an important part of the innovation infrastructure of the Novosibirsk region. In this article the authors are formulated priorities for the development of an innovative economy: The promotion of investment growth in production infrastructure and innovation, increasing the orientation of research institutions to the needs of the real economy, the development of entrepreneurship in all sectors of the economy and the creation of necessary conditions. The article considers the key elements of innovation infrastructure. Also program "Development of high-tech industry and which Technopark "Novosibirsk" implements the this article is given a brief description of the complex target innovation in the industry to the city of Novosibirsk in 2020", in concept of technopark of distributed type, when the Technopark is built in the form of structural and autonomous innovation and technology centers established by the territorial-branch principle in conjunction with partner organizations. The analysis of the stories of success (and failure) of residents of Technopark is described in this article. Based on this analysis, which highlights the main factors contributing to the achievement of commercially meaningful results. These include training as an essential component of the innovation infrastructure. Describes the international educational programs implemented by the Innovative Technology Center "Education" at the Novosibirsk State University of Economics and Management. It is noted that the most important result of the operation of Technopark "Novosibirsk" was working out a model of public-private partnership that has allowed Technopark flourish, creating a network of specialized centers of innovation and technology. Finally the authors conclude that at the present time in Russia on almost all the basic elements of support for innovative entrepreneurship are created. At the same time a significant part of the difficulties cause problems originating from the external environment of business innovation 展开更多
关键词 innovation infrastructure start-up projects technology transfer experience of technopark public-private partnership technology commercialization Gate2RuBIN project
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High-Level Nuclear Wastes and the Environment: Analyses of Challenges and Engineering Strategies
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作者 Mukhtar Ahmed Rana 《World Journal of Nuclear Science and Technology》 2012年第3期89-105,共17页
The main objective of this paper is to analyze the current status of high-level nuclear waste disposal along with presentation of practical perspectives about the environmental issues involved. Present disposal design... The main objective of this paper is to analyze the current status of high-level nuclear waste disposal along with presentation of practical perspectives about the environmental issues involved. Present disposal designs and concepts are analyzed on a scientific basis and modifications to existing designs are proposed from the perspective of environmental safety. A new concept of a chemical heat sink is introduced for the removal of heat emitted due to radioactive decay in the spent nuclear fuel or high-level radioactive waste, and thermal spikes produced by radiation in containment materials. Mainly, UO2 and metallic U are used as fuels in nuclear reactors. Spent nuclear fuel contains fission products and transuranium elements which would remain radioactive for 104 to 108years. Essential concepts and engineering strategies for spent nuclear fuel disposal are described. Conceptual designs are described and discussed considering the long-term radiation and thermal activity of spent nuclear fuel. Notions of physical and chemical barriers to contain nuclear waste are highlighted. A timeframe for nuclear waste disposal is proposed and time-line nuclear waste disposal plan or policy is described and discussed. 展开更多
关键词 HIGH-LEVEL NUCLEAR WASTE NUCLEAR WASTE CONTAINMENT and Disposal Environment Conceptual Model Designs RADIOACTIVITY Damage Chemical Heat SINK
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Survey on the Loss Function of Deep Learning in Face Recognition
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作者 Jun Wang Suncheng Feng +1 位作者 Yong Cheng Najla Al-Nabhan 《Journal of Information Hiding and Privacy Protection》 2021年第1期29-45,共17页
With the continuous development of face recognition network,the selection of loss function plays an increasingly important role in improving accuracy.The loss function of face recognition network needs to minimize the... With the continuous development of face recognition network,the selection of loss function plays an increasingly important role in improving accuracy.The loss function of face recognition network needs to minimize the intra-class distance while expanding the inter-class distance.So far,one of our mainstream loss function optimization methods is to add penalty terms,such as orthogonal loss,to further constrain the original loss function.The other is to optimize using the loss based on angular/cosine margin.The last is Triplet loss and a new type of joint optimization based on HST Loss and ACT Loss.In this paper,based on the three methods with good practical performance and the joint optimization method,various loss functions are thoroughly reviewed. 展开更多
关键词 Loss function face recognition orthogonality loss ArcFace the joint loss
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Microscopic model for chemical etchability along radiation damage paths in solids
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作者 Mukhtar Ahmed RANA 《Nuclear Science and Techniques》 SCIE CAS CSCD 2008年第3期174-177,共4页
It would be very interesting to develop a picture about removal of atoms from the radiation damaged paths or latent nuclear tracks and undamaged bulk material in track detectors. Here, theory of chemical etching is de... It would be very interesting to develop a picture about removal of atoms from the radiation damaged paths or latent nuclear tracks and undamaged bulk material in track detectors. Here, theory of chemical etching is described briefly and a new model for chemical etching along radiation damaged paths in solids is developed based on basic scientific facts and valid assumptions. Dependence of chemical etching on radiation damage intensity and etching conditions is discussed. A new parameter for etching along radiation damaged paths is introduced, which is useful for investigation of relationship between chemical etchability and radiation damage in a solid. Results and discussion presented here are also useful for further development of nuclear waste immobilization. 展开更多
关键词 固态径迹探测器 晶体缺陷 辐射损伤 固体
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Challenges in spent nuclear fuel final disposal:conceptual design models
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作者 Mukhtar Ahmed RANA 《Nuclear Science and Techniques》 SCIE CAS CSCD 2008年第2期117-120,共4页
<正>The disposal of spent nuclear fuel is a long-standing issue in nuclear technology.Mainly,UO_2 and metallic U arc used as a fuel in nuclear reactors.Spent nuclear fuel contains fission products and transurani... <正>The disposal of spent nuclear fuel is a long-standing issue in nuclear technology.Mainly,UO_2 and metallic U arc used as a fuel in nuclear reactors.Spent nuclear fuel contains fission products and transuranium elements,which would remain radioactive for 10~4 to 10~8 years.In this brief communication,essential concepts and engineering elements related to high-level nuclear waste disposal are described.Conceptual design models are described and discussed considering the long-time scale activity of spent nuclear fuel or high level waste.Notions of physical and chemical barriers to contain nuclear waste are highiightened.Concerns regarding integrity,self-irradiation induced decomposition and thermal effects of decay heat on the spent nuclear fuel are also discussed.The question of retrievability of spent nuclear fuel after disposal is considered. 展开更多
关键词 核燃料 概念设计模型 自我辐射分解 热反应
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Interval Type-2 Fuzzy Model for Intelligent Fire Intensity Detection Algorithm with Decision Making in Low-Power Devices
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作者 Emmanuel Lule Chomora Mikeka +1 位作者 Alexander Ngenzi Didacienne Mukanyiligira 《Intelligent Automation & Soft Computing》 2023年第10期57-81,共25页
Local markets in East Africa have been destroyed by raging fires,leading to the loss of life and property in the nearby communities.Electrical circuits,arson,and neglected charcoal stoves are the major causes of these... Local markets in East Africa have been destroyed by raging fires,leading to the loss of life and property in the nearby communities.Electrical circuits,arson,and neglected charcoal stoves are the major causes of these fires.Previous methods,i.e.,satellites,are expensive to maintain and cause unnecessary delays.Also,unit-smoke detectors are highly prone to false alerts.In this paper,an Interval Type-2 TSK fuzzy model for an intelligent lightweight fire intensity detection algorithm with decision-making in low-power devices is proposed using a sparse inference rules approach.A free open–source MATLAB/Simulink fuzzy toolbox integrated into MATLAB 2018a is used to investigate the performance of the Interval Type-2 fuzzy model.Two crisp input parameters,namely:FIT and FIG��are used.Results show that the Interval Type-2 model achieved an accuracy value of FIO�=98.2%,MAE=1.3010,MSE=1.6938 and RMSE=1.3015 using regression analysis.The study shall assist the firefighting personnel in fully understanding and mitigating the current level of fire danger.As a result,the proposed solution can be fully implemented in low-cost,low-power fire detection systems to monitor the state of fire with improved accuracy and reduced false alerts.Through informed decision-making in low-cost fire detection devices,early warning notifications can be provided to aid in the rapid evacuation of people,thereby improving fire safety surveillance,management,and protection for the market community. 展开更多
关键词 Interval type-2(IT2)fuzzy systems mean absolute error(MAE) mean square error(MSE) root mean square
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Cascade-exciton model analysis of level density parameter dependence in proton induced fission cross sections of some sub-actinide nuclei
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作者 Zafar Yasin Warda Iram +1 位作者 Muhammad Asghar M. Ikram Shahza 《Chinese Physics C》 SCIE CAS CSCD 2011年第11期1013-1016,共4页
Fission cross sections strongly depend on the ratio of the level density parameter in fission to neutron emission, af/an . In this work, a cascade-exciton model implemented in the code CEM95 has been used to observe t... Fission cross sections strongly depend on the ratio of the level density parameter in fission to neutron emission, af/an . In this work, a cascade-exciton model implemented in the code CEM95 has been used to observe this effect for proton induced fission cross sections of tungsten, lead and bismuth. The method was employed using different level density parameter ratios for each fission cross section calculation. The calculated fission cross sections are compared with the available experimental data in the literature. It has been observed that a change of the ratio of the level density parameter, af/an , is necessary with the incident energy of the proton, to best estimate the fission cross sections in CEM95. 展开更多
关键词 CEM95 fission cross sections level density parameter
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