Generation of OAM Waves and Analysis of Mode Purity for 5G Sub-6 GHz Applications

This article presents the generation of Orbital AngularMomentum(OAM)vortex waves with mode 1 using Uniform Circular Array(UCA)antenna.Two different designs,namely,UCA-1(4-element array antenna)and UCA-2(8-element array antenna),were designed and fabricated using FR-4 substrate to generate OAM mode 1 at 3.5 GHz(5G mid-band).The proposed antenna arrays comprised rectangular microstrip patch elements with inset fed technique.The elements were excited by a carefully designed feeding phase shift network to provide similar output energy at output ports with desired phase shift value.The generated OAM waves were confirmed by measuring the null in the bore sight of their 2D radiation patterns,simulated phase distribution and intensity distribution.The measurement results agree well with the simulation results.Moreover,a detailed mode purity analysis of the generated OAM waves was carried out considering different factors.The investigation found that the greater the number of elements,the higher the purity of the generated OAM wave.Compared with other previous works,the proposed antenna design of this paper is very simple to design and fabricate.In addition,the proposed antennas are compact in design even at lower frequency band with very wide bandwidth to meet the requirements of 5G mid-band applications.

Bio-effects of 5th generation electromagnetic waves on organs of human beings

Objectives:The uses of devices of electromagnetic waves(EMWs)are increasing day by day.Similarly,the generation of the waves is increasing.The frequency spectrum of the generation of waves is also increased.In this manuscript,an analysis of the high frequency EMWs has been made by the electric fields generated due to the exposure of 5th generation(5 G)of mobile phones.Methods:Due to the emission of waves from the towers,the electric field is generated around the transmission tower of mobile phones.The electric fields are computed by the power of the transmission tower.The electric fields across the biological tissues/cells are also computed when the EMWs penetrate inside the body.The electric fields are made across the organs of different depths inside the body.Results:The induced electric fields inside the organs of the human beings are responsible for the absorption of energy from high frequency EMWs.The absorbed amount of energy from high frequency waves may become the cause of harmful effects on the life of organs of human beings.Conclusion:In this manuscript,after analysis of the computed electric fields inside the organs of human beings,it is concluded that the EMWs of 5 G spectrum of mobile phone towers may more harmful for the life of organs as 4th generation(4 G)spectrum of mobile phone waves.The energy absorption by the 4 G spectrum is lower than 5 G spectrum due to the range of frequency of waves.The effects on the pancreas,retina,skin,intestine,spleen,stomach and uterus are more than low water content organs like nails,bone,teeth etc.

Comprehensive applicability evaluation of four precipitation products at multiple spatiotemporal scales in Northwest China

Precipitation plays a crucial role in the water cycle of Northwest China.Obtaining accurate precipitation data is crucial for regional water resource management,hydrological forecasting,flood control and drought relief.Currently,the applicability of multi-source precipitation products for long time series in Northwest China has not been thoroughly evaluated.In this study,precipitation data from 183 meteorological stations in Northwest China from 1979 to 2020 were selected to assess the regional applicability of four precipitation products(the fifth generation of European Centre for Medium-Range Weather Forecasts(ECMWF)atmospheric reanalysis of the global climate(ERA5),Global Precipitation Climatology Centre(GPCC),Climatic Research Unit gridded Time Series Version 4.07(CRU TS v4.07,hereafter CRU),and Tropical Rainfall Measuring Mission(TRMM))based on the following statistical indicators:correlation coefficient,root mean square error(RMSE),relative bias(RB),mean absolute error(MAE),probability of detection(POD),false alarm ratio(FAR),and equitable threat score(ETS).The results showed that precipitation in Northwest China was generally high in the east and low in the west,and exhibited an increasing trend from 1979 to 2020.Compared with the station observations,ERA5 showed a larger spatial distribution difference than the other products.The overall overestimation of multi-year average precipitation was approximately 200.00 mm and the degree of overestimation increased with increasing precipitation intensity.The multi-year average precipitation of GPCC and CRU was relatively close to that of station observations.The trend of annual precipitation of TRMM was overestimated in high-altitude regions and the eastern part of Lanzhou with more precipitation.At the monthly scale,GPCC performed well but underestimated precipitation in the Tarim Basin(RB=-4.11%),while ERA5 and TRMM exhibited poor accuracy in high-altitude regions.ERA5 had a large bias(RB≥120.00%)in winter months and a strong dispersion(RMSE≥35.00 mm)in summer months.TRMM showed a relatively low correlation with station observations in winter months(correlation coefficients≤0.70).The capture performance analysis showed that ERA5,GPCC,and TRMM had lower POD and ETS values and higher FAR values in Northwest China as the precipitation intensity increased.ERA5 showed a high capture performance for small precipitation events and a slower decreasing trend of POD as the precipitation intensity increased.GPCC had the lowest FAR values.TRMM was statistically ineffective for predicting the occurrence of daily precipitation events.The findings provide a reference for data users to select appropriate datasets in Northwest China and for data developers to develop new precipitation products in the future.

Radio Propagation and Wireless Coverage of LSAA-Based 5G Millimeter-Wave Mobile Communication Systems

Millimeter-wave(mm Wave) communications will be used in fifth-generation(5G) mobile communication systems, but they experience severe path loss and have high sensitivity to physical objects, leading to smaller cell radii and complicated network architectures. A coverage extension scheme using large-scale antenna arrays(LSAAs) has been suggested and theoretically proven to be cost-efficient in combination with ultradense small cell networks. To analyze and optimize the LSAA-based network deployments, a comprehensive survey of recent advances in statistical mmWave channel modeling is first presented in terms of channel parameter estimation, large-scale path loss models, and small-scale cluster models. Next, the measurement and modeling results at two 5G candidate mmWave bands(e.g., 28 GHz and 39 GHz) are reviewed and compared in several outdoor scenarios of interest, where the propagation characteristics make crucial contributions to wireless network designs. Finally, the coverage behaviors of systems employing a large number of antenna arrays are discussed, as well as some implications on future mmWave cellular network designs.

Computer Modelling of Compact 28/38 GHz Dual-Band Antenna for Millimeter-Wave 5G Applications

A four-element compact dual-band patch antenna having a common ground plane operating at 28/38 GHz is proposed formillimeter-wave communication systems in this paper.Themultiple-input-multiple-output(MIMO)antenna geometry consists of a slotted ellipse enclosed within a hollow circle which is orthogonally rotated with a connected partial ground at the back.The overall size of the four elements MIMO antenna is 2.24λ×2.24λ(at 27.12GHz).The prototype of four-element MIMOresonator is designed and printed using Rogers RTDuroid 5880 withε_(r)=2.2 and loss tangent=0.0009 and having a thickness of 0.8 mm.It covers dual-band having a fractional bandwidth of 15.7%(27.12-31.34 GHz)and 4.2%(37.21-38.81 GHz)for millimeter-wave applications with a gain of more than 4 dBi at both bands.The proposed antenna analysis in terms ofMIMOdiversity parameters(Envelope Correlation Coefficient(ECC)and Diversity Gain(DG))is also carried out.The experimental result in terms of reflection coefficient,radiation pattern,gain and MIMOdiversity parameter correlates very well with the simulated ones that show the potential of the proposed design for MIMO applications at millimeter-wave frequencies.

Prospects of Technological Improvement of Nuclear and Environmental Safety of World Energy

Today, the most urgent problem of the existing and future nuclear power industry is to ensure the nuclear and environmental safety of the operation of nuclear power reactor units (NPPs) and nuclear power plants (NPPs). It is solved thanks to the application of deeply echeloned protection and an anti-accident complex of methods and means for effective control of the operation of active reactor zones (AZR). However, the danger of existing NPPs in the world from time to time manifests itself in the form of severe post-project accidents and catastrophes with the release into the environment of a significant amount of radioactive materials dangerous for all living things. The results of the analysis show that the unconditional fulfillment of the main requirements of nuclear environmental safety and biocompatibility is possible only in the so-called wave nuclear reactor of the G-V generation, which, unlike reactors of the previous generations III, II+ and IV, does not require supercritical loading of the core with nuclear fuel. In the active zone of this reactor, nuclear-physical processes governed by physical law are implemented, which exclude the operator’s participation in regulating the reactivity of the reactor’s active zone, which makes it the reactor with the highest level of nuclear and environmental safety today, which is based on the principles of so-called internal safety, free from the human factor. The possibility of burning nuclear fuel based on U238 and Th232 in it expands the reserves of energetic nuclear fuel almost to inexhaustibility. The technology of nuclear reactors of the G5 generation through the secondary use of spent irradiated nuclear fuel (SNF) for the production of energy and energy raw materials with simultaneous burning of it to an environmentally safe state is able to quickly reduce the available stocks and further production of dangerous SNF, guarantee the nuclear and environmental safety of NPPs with reactors G5 and to technologically make nuclear post-project accidents and disasters impossible at the level of physical law with the complete elimination of the human factor.

The Impact of Internet of Things Supported by Emerging 5G in Power Systems: A Review

The Internet of Things(IoT)is playing an important role in providing access to affordable,clean and green energy worldwide through the use of smart devices.The current electric power networks will be more reliable,secure,flexible and durable by implementing IoT in power systems.This paper presents a brief discussion about IoT contributions in the development of power systems from a generation,transmission,distribution and consumption point of view.5G cellular networks have a great potential for the development of IoT technology.Additionally,5G cellular networks can be instrumental in supporting the greater communication needs of IoT.This review provides a comprehensive analysis about the role of 5G cellular networks in the growth of IoT technology and power systems.Large amounts of data will be generated due to the incorporation of renewable energy,deployment of the smart grid and the improvements to the electricity market.In this way,in order to realize the connection between things and people,things and things and people and people in power systems,it is essential to apply IoT in power systems.In this case,5G is providing numerous advantages to Power IoT(PIoT)by offering greater opportunities in progress and improvements;however,there are also numerous challenges with the deployment of 5G in PIoT.Finally,this review article provides an overview of the role,implications and challenges of 5G in PIoT.

风格的代际转移:中国第五代、第六代导演的计量学研究

将计量学方法应用于第五代第六代电影的研究中,可以把风格的代际转移进行一定程度的可视化呈现。第五代电影风格更统一,青睐宏大叙事与深刻主题,表现的人物或异于常人充满英雄色彩,或是帝王将相,整体节奏也较快。相较于第五代,第六代电影风格更加多元,很难用简洁确切的语言进行概括。然而,生活化叙事、较长的镜头以及平凡甚至边缘的人物可以概括大多数第六代导演的作品特点。

论中国第五代导演的现代电影创造

中国第五代导演的现代电影创造主要体现在四个方面:第一,第五代导演的电影极大地推进了中国电影的现代化进程,丰富并深化了中国电影的现代性内涵;第二,第五代导演的影像本体美学在中国影坛独辟蹊径,是对中国电影叙事艺术的一次重大革新;第三,第五代导演的影像语言融写实与写意、再现与表现为一体,画面构图、光影、色彩,以及镜头运用等具有较高的审美价值;第四,在形象塑造上,第五代导演普遍经历了从写意到写人、从意象营造到人物刻画的转变过程,创造了一系列意蕴丰富的艺术意象和成功的人物形象。

近30年来中国第五代电影价值取向的变化

近30年来第五代电影价值取向出现阶段性变化:1983年至1999年,第五代导演主要追求艺术价值;2000年至2010年,大部分第五代导演主要追求商业价值,少量第五代导演仍然主要追求艺术价值;2010年至今,第五代导演电影艺术价值与商业价值并重。近30年来中国第五代电影主要价值取向如此,其间也有小的起伏。其变化的原因、表现与作用都是十分明显的。电影既是艺术品,也是商品,因而既具有艺术价值,也具有商业价值。因此,理想的方式是电影的艺术价值与商业价值并重。

反思中国与制造中国——论第五代的民俗电影

1980年以来,民俗电影一直是第五代重要的创作题材。从《黄土地》、《红高粱》到《霸王别姬》,第五代电影大都体现为民俗奇观包装的民族寓言。第五代的民俗电影显示了一种别样的现代性景观,是当代中国的现代化实践和体验的文化镜像,反映了在本土与全球、己域与群域、传统与现代等二元对立范畴间交叉辉映所形成的、具有时空特定性——后革命中国的现代性想象。

论第五代导演与西部电影的艺术叠交

第五代导演初登影坛之时,便将自己的艺术触角大多伸向了对中国西部民族、历史与文化的反思与解读,实现了与当时正在走向兴盛的西部电影思潮的艺术叠交。第五代导演不仅使得西部电影更加富于创新性和开拓性,同时也使自身在对西部电影艺术的探索中更加趋于成熟和完善。

从先锋探索到走向市场——论中国第五代电影导演的创作发展及贡献

中国第五代电影导演自1984年以不同凡响的先锋姿态登上影坛以来,迄今已有30年了。在影坛潮起潮落中,他们的创作经历了从先锋探索到走向市场的发展过程,在艺术片、娱乐片和主旋律影片的创作领域,都有创新探索和突出贡献。他们的电影创作道路从一个侧面反映了中国电影的创新发展和坎坷起伏的历史过程。当下,第五代导演的创作也面临着一些新的问题和挑战。因此,回顾第五代导演的创作之路,总结其经验教训及对中国电影发展的贡献,无论是对于第五代导演以后创作的持续拓展,还是对于当下国产电影创作健康有序的发展,抑或是对于深化中国电影史的研究来说,都是非常必要和十分有益的。

20世纪80年代的新启蒙运动与第五代导演的创作

步入二十世纪八十年代,中国大陆掀起了一场新启蒙运动,以人道主义和主体性为理论武器对文革进行了深入的批判与反思。在此期间出现的第五代导演深受这场运动影响,他们以自己的电影创作展开对人道主义和电影主体性的探索,开创了崭新的电影美学,并在促使中国电影完成向现代电影转变的同时,将中国电影带入了世界影坛的中心。

1980年代第五代导演的视觉革命与艺术贡献——以1987年的《红高粱》为例

《红高粱》作为第五代导演的代表性作品之一,在1980年代的电影历史进程中具有双重价值和意义的革命性:对新中国电影表现模式的突破和文本本身的创新构建。对前者而言,其突破更多的体现在颠覆性和重构性上,就后者而言,它为1990年代社会转型期的中国电影提供了良好的思想创新基础。

个性改编与影像凸显——论“第五代”导演的电影文学改编

"第五代"导演们开创了中国电影的新时代,他们用新的理念进行电影创作实践,尤其在电影影像方面独树一帜。"第五代"的成功之作大多由文学作品改编而来,他们对文学作品的青睐和倚重,很大程度上体现了现代电影与文学间的一种对话。"第五代"导演具有国际化视野,正在渐近于西方某些艺术家把文学原作看作是一堆未经加工过的素材的改编观念。"第五代"导演在对文学作品的改编过程中始终贯穿着自己对电影本质的理解和自己独特的思想,他们在文学改编的影片中留下了自己创作个性的深刻印记,使其真正成为电影化的、个性化的作品。

论我国二十世纪八十年代的探索电影

20世纪 80年代我国的电影创作出现了前所未有的大胆探索景象。以张艺谋为代表的第五代导演扛起了反叛传统创作理念、创作原则的大旗 ,在审美观上追求真实 ,在哲学观方面对人进行深刻的剖析 ,表现出自在、坦然的生命意识 ,在创作原则方面 ,大胆地强化观念、细节、造型 ,淡化主题、情节、人物。这种探索创造了一个崭新的银幕时空 ,就探索创新而言 ,无疑具有进步的意义 ,但是作为电影———这种大众的艺术 ,过分追求创作主题的哲学理性、创作手段的主观个性 。

论新生代与第五代导演影片中的“父性”价值比较及意义

新生代导演作为中国影坛崛起的新兴力量,正在以其独特的文化内涵、艺术感知改变着当代中国影坛的面貌,他们不同于第五代导演站在历史的角度俯瞰人生,而是将镜头对准普通人,关注现实生活中的悲喜人生,从而探索现代社会普遍存在的生存焦虑。通过对两代导演作品中的"父性"价值比较,反映出新生代导演的创作规律,即他们不再像第五代导演那样把"父性"作为一种隐喻和反叛意愿的投射体,而是试图理性地认识父性,还原"父性"的伦理和普世价值,同时也折射出新生代导演在探索现代社会中男性的生存焦虑和主体构建方面作出的努力。

重提“第五代”——一个未完结的话题

第五代导演及其电影作品作为新时期以来重要的电影现象,一直备受关注。而其自上世纪80～90年代以来几曾遭遇"衰亡说"的困扰也表明,对"第五代"的认识始终存在误区或分歧。通过对其概念的廓清和梳理发现,第五代在经历了80年代艺术探索新电影的辉煌与落寞后,并没有销声匿迹,而是经过适当的调整,在90年代继续走向其影响与声誉的另一巅峰;进入新世纪,第五代作为"代群"的概念和特征确已明显消退,但其成员仍在以更加个人化的行为从事着电影创作。

论新时期中国电影的民族化演进过程——以第三、四、五代导演为例

中国电影事业自新时期以来取得了辉煌的成就,不但涌现大量的佳片力作,而且还不断在世界电影舞台上获得声誉。这种良好态势的出现除了是因为我们吸收了世界电影的先进经验,更为重要的是由于这一时期电影在处理民族化问题方面上成就显著。因而,从民族化进程的角度并以新时期电影的主要制作者———第三、四、五代导演为例来探讨这一时期电影的得失就具有深刻的现实意义。