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Highly nonlinear bored core hexagonal photonic crystal fiber(BC-HPCF)with ultra-high negative dispersion for fiber optic transmission system

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Frontiers of Optoelectronics 2020年第4期13卷 433-440页

作者： Md.Mostafa FARUK Nazifa Tabassum KHAN Shovasis Kumar BISWAS Department of Electrical and Electronic Engineering Independent University BangladeshDhakaBangladesh

In this paper,we propose a bored core hexagonal photonic crystal fiber(BC-HPCF)which obtains ultra-high negative dispersion and large nonlinearity simultaneously.The aim of the proposed design is to achieve the desired optical properties by using circular air holes only to make the fiber simple and manufacturable.To investigate the light guiding properties of the proposed BC-HPCF,finite element method(FEM)with circular perfectly matched boundary layer(PML)is used.According to numerical simulation,it is possible to obtain a large value of negative dispersion of-2102 ps·nm^(-1)•km^(-1)and large value of nonlinearity of 111.6 W^(-1)·km^(-1)at optimum wavelength of 1550 nm.In addition,±2%deviation in optical characteristics is evaluated and reported in order to study the practical feasibility of the proposed BC-HPCF.The large negative dispersion and high nonlinearity of our proposed design make it a strong candidate for optical broadband communication,super continuum generation,and sensing.

关键词： photonic crystal fiber(PCF) dispersion nonlinearity optical broadband communication

The role of GRP81 lactate receptor in synaptic transmission regulation: does it enhance endocytosis?

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Neural Regeneration Research 2022年第12期17卷 2657-2658页

作者： Sergei V.Fedorovich Tatsiana V.Waseem Department of Biochemistry Belarusian State UniversityMinskBelarus independent researcher MinskBelarus

The brain is an expensive tissue in terms of energy consumption.It composes about 2%of body mass and consumes about 20%of all oxygen and calories(Fedorovich and Waseem,2018).For neurons,glucose is the primary energy substrate,although they are able to use ketone bodies,pyruvate and lactate(Fedorovich and Waseem,2018).All these compounds can be metabolized directly in the Krebs cycle,bypassing glycolysis.Hence,they are often termed non-glycolytic energy substrates.Out of all potential non-glycolytic substrates,lactate is the most physiological(Magistretti and Allaman,2018).Ketone bodies could reach concentrations in blood plasma and cerebrospinal fluid which are sufficient to meet metabolic demands of neurons only under specific non-physiological conditions,e.g.,ketogenic diet and starvation,or during suckling.In contrast,the normal plasma level of lactate is about 1.5 mM and can reach 20 mM during intensive physical exercise.

关键词： ketone glycol cycle

Toward a semiotic pyramid:language studies,AI,and knowledge exchange economy

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Language and Semiotic Studies 2023年第3期9卷 393-407页

作者： Felix Poschinger Robert Coon university of Hamburg Hamburg 20148 Germany independent Hamburg Germany

This paper addresses the interrelation between AI and language studies in the(digital)humanities in the context of knowledge exchange economies.We propose a three-dimensional semiotic model(pyramid)that includes AI as an active agent in meaning-creation into the sign system of communication and test its validity on autocompletion and predictive texting.We,therefore,analyzed 360 million tweets on COvID-19 over a period of 2 years and focused on the time-dependent shift of language use in the positive and negative extremes correlating to significant external events.The data suggest that digital language use has significantly changed over the course of the pandemic.Feedback loops are created between Al,utterance,and external reality that fossilize preconceived notions into textual isoglosses by suggesting and completing text entries.We thus argue that AI subtly changes the perception of reality by influencing the choice of wording.To mitigate the impact of AI in meaning-creation,we highlight the structural precautions undertaken by providers;we argue,however,that the(digital)humanities may re-emphasize their intrinsic value within the economy of knowledge exchange according to the subject-specific insights they may provide for language use and AI.

关键词： AI digital humanities meaning-creation semiotic pyramid

Preserving Privacy of Software-Defined Networking Policies by Secure Multi-Party Computation

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Journal of Computer Science & Technology 2020年第4期35卷 863-874页

作者： Maryam Zarezadeh Hamid Mala Homa Khajeh Faculty of Computer Engineering University of IsfahanIsfahan ***Iran independent Researcher Isfahan ***Iran

In software-defined networking(SDN),controllers are sinks of information such as network topology collected from switches.Organizations often like to protect their internal network topology and keep their network policies private.We borrow techniques from secure multi-party computation(SMC)to preserve the privacy of policies of SDN controllers about status of routers.On the other hand,the number of controllers is one of the most important concerns in scalability of SMC application in SDNs.To address this issue,we formulate an optimization problem to minimize the number of SDN controllers while considering their reliability in SMC operations.We use Non-Dominated Sorting Genetic Algorithm II(NSGA-II)to determine the optimal number of controllers,and simulate SMC for typical SDNs with this number of controllers.Simulation results show that applying the SMC technique to preserve the privacy of organization policies causes only a little delay in SDNs,which is completely justifiable by the privacy obtained.

关键词： software-defined networking (SDN) privacy secure multi-party computation (SMC) structure function multi-objective optimization

What would a US green hydrogen energy economy look like?

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Clean Energy 2023年第5期7卷 1148-1172页

作者： Thomas Tonon independent researcher Ph.D.Aerospace and Mechanical SciencesPrinceton University1971.11 Bolfmar AvenuePrinceton JunctionNJ 08550USA

Detailed description is given for a hypothetical US hydrogen economy with solar and wind energy supplying virtually all current energy needs and with electrolytic hydrogen the energy carrier and storage medium.Fossil fuels provide nonfuel products(plastics,chemicals,cement and asphalt).Only current technologies are considered and hydrogen storage accommodates generation intermit-tency and variability,using pit storage of high-pressure vessels in open air,yielding daily storage round-trip energy installation costs of 722 and 538$/kWh for electric and thermal,respectively;and for power,2351 and 2240$/kW for electric and thermal,respectively.For long-duration storage,the costs are 94.1 and 23.8$/kWh and 937 and 845$/kW,respectively.Increased energy generation 20%over baseline accommodates low-season generation,obviates much required storage and ensures that reserves are topped off;96%of US 2022 total energy consumption is provided for.In the default scenario(demand energy portions:half photovoltaic,quarter on-shore wind and quarter offshore wind),the surface area for the farms(including offshore surface)requires~4.6%of the US 48-state land area.About 350 pit storage sites provide both daily and long-duration storage,with the latter accounting for complete loss of generation for 4 days over a quarter of the nation.Hydrogen pipelines and a renewed electric grid transmit and distribute energy.The installation cost of the public infrastructure is~$27.8 trillion for the default scenario.Alternative scenarios show significant in-frastructure and cost savings when batteries are used for transportation and/or utility storage,provided current insufficiencies can be overcome.Broadly,cost levels in money,surface and infrastructure are within existing levels already achieved in historical events and modern living.

关键词： hydrogen economy renewable energy hydrogen storage hydrogen pipelines sustainable net zero

Towards Building Direct Educational Partnership:The Foundation of Shanxi university in 1902

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Frontiers of Education in China 2014年第2期9卷 188-210页

作者： Aisi LI independent Scholar

The foundation of Shanxi university is a prime example of the collaborative efforts in higher education between the Chinese and British in late Qing China(1842-1912).Both sides made compromises,with the Chinese adapting their ideas of educational sovereignty,and the British agreeing to work under the supervision of the local government.Such a collaboration was made possible by the individual personalities of the two founders and their visions for China’s higher education.The dual structure of the university,with one department to teach Chinese learning and the other to teach Western learning,showed that,at a local and personal level,these officials and missionaries opted for direct cooperation,despite the myriad changes and upheavals following the Boxer Movement.In addition,by allowing foreign missionaries into critical roles in a government university,the principle of ti-yong dualism was gradually being adapted.The formation of Shanxi university not only demonstrates the dynamics of the Sino-Western educational relationship and the roles individuals played in it,but also stimulates reflection on China’s contemporary cross-border partnerships in higher education.

关键词： Shanxi university Sino-foreign cooperation missionary education cross-border partnership higher education reform

The aggregate and sectoral time‑varying market efficiency during crisis periods in Turkey:a comparative analysis with COVID‑19 outbreak and the global financial crisis

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Financial Innovation 2023年第1期9卷 2165-2189页

作者： Deniz Erer Elif Erer Selim Güngör School of Applied Sciences Manisa Celal Bayar UniversityManisaTurkey independent Researcher IzmirTurkey Resadiye Vocational School Tokat Gaziosmanpasa UniversityTokatTurkey

This study aims to examine the time-varying efficiency of the Turkish stock market’s major stock index and eight sectoral indices,including the industrial,financial,service,information technology,basic metals,tourism,real estate investment,and chemical petrol plastic,during the COVID-19 outbreak and the global financial crisis(GFC)within the framework of the adaptive market hypothesis.This study employs multifractal detrended fluctuation analysis to illustrate these sectors’multifractality and short-and long-term dependence.The results show that all sectoral returns have greater persis-tence during the COVID-19 outbreak than during the GFC.Second,the real estate and information technology industries had the lowest levels of efficiency during the GFC and the COVID-19 outbreak.Lastly,the fat-tailed distribution has a greater effect on multifractality in these industries.Our results validate the conclusions of the adaptive market hypothesis,according to which arbitrage opportunities vary over time,and contribute to policy formulation for future outbreak-induced economic crises.

关键词： MF-DFA Adaptive market hypothesis Global financial crisis COVID-19 outbreak Sectoral indices

The East–West Divide in Response to COVID-19

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Engineering 2021年第7期7卷 936-947页

作者： Dean T.Jamison Kin Bing Wu Department of Epidemiology and Biostatistics University of CaliforniaSan FranciscoCA 98158USA independent Consultant AthertonCA 94027USA

Coronavirus disease 2019(COVID-19)deaths per million population in the countries of the West had often exceeded those in the countries of the East by factor of 100 by May 2021.In this paper,we refer to the West as represented by the United States plus the five most populous countries of Western Europe(France,Germany,Italy,Spain,and the United Kingdom),and the East as the 15 countries in East Asia and Oceania that are members of the Regional Comprehensive Economic Partnership,RCEP(Australia,Brunei,Cambodia,China,Indonesia,Japan,the Republic of Korea,Laos,Malaysia,Myanmar,New Zealand,Philippines,Singapore,Thailand,and Vietnam).This paper argues that currently available information points to the factors most responsible for the East–West divide.Warnings by early January 2020 about an atypical viral pneumonia in Wuhan,China,prompted rapid responses in many jurisdictions in East Asia.Publication of the virus’s genome on 10 January 2020 provided essential information for making diagnostic tests and launching vaccine development.China’s lockdown of Wuhan on 23 January 2020 provided a final,decisive signal of the danger of the new disease.By late March 2020,China had fully controlled its epidemic,and many other RCEP countries had taken early and decisive measures,including restrictions on travel,that aborted serious outcomes.Inaction during the critical month of February 2020 in the United States and most other Western countries allowed the disease to take hold and spread.In both the East and the West,stringent population-wide non-pharmaceutical interventions were widely implemented at great cost to societies,economies,and school systems.Without these measures,the outcomes could have been even worse.Most countries in the East also implemented tightly focused policies to isolate infectious individuals.Even today,most countries in the West allow infectious individuals to mingle with their families,coworkers,and communities.Much of the East–West divide plausibly results from failure in the West to implement the basic public

关键词： Coronavirus disease 2019 Isolation Non-pharmaceutical interventions Pandemic Vaccination

Numerical modeling and spatial stability analysis of the wall jet flow of nanofluids with thermophoresis and brownian effects

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Propulsion and Power Research 2019年第3期8卷 210-220页

作者： Amin Jafarimoghaddam Fatemeh Shafizadeh independent Researcher TehranIran Department of Chemical Engineering Babol Noshirvani University of TechnologyBabolIran

The present work describes similarity solution to a general scheme for the wall jet flow of nanofluids,accounting both the similarity branches(say upper and lower),allowed with respect to the suction and moving wall conditions in the context of Glauert type e-jets.Before proceeding with this,a spatial stability analysis is performed to check the stability of the similarity modes.Results indicated that the upper similarity branch is possibly stable;whilst,the lower branch is not likely to reside in actual physics.The governing transport equations of mass and energy subject to a general two-phase modeling framework were transformed into similarity equations.The involved equations were then solved numerically employing the standard 4th order Runge-Kutta together with shooting technique.The influence of the involved parameters is shown graphically and in a detailed manner.In the last section,it is presented closed-form algebraic solution to the energy equation for the base fluids with a general convective boundary condition.

关键词： Wall jet flow of nanofluids Two-phase modeling Spatial stability analysis Similarity solution Numerical modeling