Future 6G communications are envisioned to enable a large catalogue of pioneering applications.These will range from networked Cyber-Physical Systems to edge computing devices,establishing real-time feedback control l...Future 6G communications are envisioned to enable a large catalogue of pioneering applications.These will range from networked Cyber-Physical Systems to edge computing devices,establishing real-time feedback control loops critical for managing Industry 5.0 deployments,digital agriculture systems,and essential infrastructures.The provision of extensive machine-type communications through 6G will render many of these innovative systems autonomous and unsupervised.While full automation will enhance industrial efficiency significantly,it concurrently introduces new cyber risks and vulnerabilities.In particular,unattended systems are highly susceptible to trust issues:malicious nodes and false information can be easily introduced into control loops.Additionally,Denialof-Service attacks can be executed by inundating the network with valueless noise.Current anomaly detection schemes require the entire transformation of the control software to integrate new steps and can only mitigate anomalies that conform to predefined mathematical models.Solutions based on an exhaustive data collection to detect anomalies are precise but extremely slow.Standard models,with their limited understanding of mobile networks,can achieve precision rates no higher than 75%.Therefore,more general and transversal protection mechanisms are needed to detect malicious behaviors transparently.This paper introduces a probabilistic trust model and control algorithm designed to address this gap.The model determines the probability of any node to be trustworthy.Communication channels are pruned for those nodes whose probability is below a given threshold.The trust control algorithmcomprises three primary phases,which feed themodel with three different probabilities,which are weighted and combined.Initially,anomalous nodes are identified using Gaussian mixture models and clustering technologies.Next,traffic patterns are studied using digital Bessel functions and the functional scalar product.Finally,the information coherence and content are analyzed.The noise content and abnormal information sequences are detected using a Volterra filter and a bank of Finite Impulse Response filters.An experimental validation based on simulation tools and environments was carried out.Results show the proposed solution can successfully detect up to 92%of malicious data injection attacks.展开更多
AIM: To investigate the relationship between gastric dysmotility,gastrointestinal hormone abnormalities, and neuroendocrine cells in gastrointestinal mucosa in patients with functional dyspepsia (FD).METHODS: Gastric ...AIM: To investigate the relationship between gastric dysmotility,gastrointestinal hormone abnormalities, and neuroendocrine cells in gastrointestinal mucosa in patients with functional dyspepsia (FD).METHODS: Gastric emptying was assessed with solid radiopaque markers in 54 FD patients, and the patients were divided into two groups according to the results, one with delayed gastric emptying and the other with normal gastric emptying. Seventeen healthy volunteers acted as normal controls. Fasting and postprandial plasma levels and gastroduodenal mucosal levels of gastrointestinal hormones gastrin, somatostatin (SS) and neurotensin (NT)were measured by radioimmunoassay in all the subjects.G cells (gastrin-producing cells) and D cells (SS-producing cells) in gastric antral mucosa were immunostained with rabbit anti-gastrin polyclonal antibody and rabbit anti-SS polyclonal antibody, respectively, and analyzed quantitatively by computerized image analysis.RESULTS: The postprandial plasma gastrin levels, the fasting and postprandial plasma levels and the gastric and duodenal mucosal levels of NT were significantly higher in the FD patients with delayed gastric emptying than in those with normal gastric emptying and normal controls. The number and gray value of G and D cells and the G cell/D cell number ratio did not differ significantly between normal controls and the FD patients with or without delayed gastric emptying.CONCLUSION: Our findings suggest that the abnormalities of gastrin and NT may play a role in the pathophysiology of gastric dysmotility in FD patients, and the abnormality of postprandial plasma gastrin levels in FD patients with delayed gastric emptying is not related to the changes both in the number and gray value of G cells and in the G cell/D cell number ratio in gastric antral mucosa.展开更多
Non-Maxwellian particle distribution functions possessing high energy tail and shoulder in the profile of distribution function considerably change the damping characteristics of the waves. In the present paper Landau...Non-Maxwellian particle distribution functions possessing high energy tail and shoulder in the profile of distribution function considerably change the damping characteristics of the waves. In the present paper Landau damping of electron plasma (Langmuir) waves and ion-acoustic waves in a hot, isotropic, unmagnetized plasma is studied with the generalized (r, q) distribution function. The results show that for the Langmuir oscillations Landau damping becomes severe as the spectral index r or q reduces. However, for the ion-acoustic waves Landau damping is more sensitive to the ion temperature than the spectral indices.展开更多
Equilibrium structures and infrared spectra of four typical molecular models of coal have been studied by density functional calculations. Combining theoretical calculations on the coal models with experimental FT-IR ...Equilibrium structures and infrared spectra of four typical molecular models of coal have been studied by density functional calculations. Combining theoretical calculations on the coal models with experimental FT-IR spectra of selected low rank perhydrous coals, a plausible molecular representation for this kind of coals was proposed, and its predicted IR spectra reasonably match the experimental observation. Calculations indicate that the cleavage of the C-C bridge bond for the coal structures considered here occurs at about 540 ℃ and the C-O ether bridge bond may break under temperature ranging from 500 to 600 ℃for the aryl-CH2-O-CH2-aryl ether bond or from 200 to 300 ℃ for the aryl-CH2-O-aryl ether bond, showing remarkable effect of the local structural environment. The coal model containing the carboxyl group may release CO2 at about 300 ℃ through the decarboxylation with a barrier of 69 kcal/mol.展开更多
The current resource allocation in 5G vehicular networks for mobile cloud communication faces several challenges,such as low user utilization,unbalanced resource allocation,and extended adaptive allocation time.We pro...The current resource allocation in 5G vehicular networks for mobile cloud communication faces several challenges,such as low user utilization,unbalanced resource allocation,and extended adaptive allocation time.We propose an adaptive allocation algorithm for mobile cloud communication resources in 5G vehicular networks to address these issues.This study analyzes the components of the 5G vehicular network architecture to determine the performance of different components.It is ascertained that the communication modes in 5G vehicular networks for mobile cloud communication include in-band and out-of-band modes.Furthermore,this study analyzes the single-hop and multi-hop modes in mobile cloud communication and calculates the resource transmission rate and bandwidth in different communication modes.The study also determines the scenario of one-way and two-way vehicle lane cloud communication network connectivity,calculates the probability of vehicle network connectivity under different mobile cloud communication radii,and determines the amount of cloud communication resources required by vehicles in different lane scenarios.Based on the communication status of users in 5G vehicular networks,this study calculates the bandwidth and transmission rate of the allocated channels using Shannon’s formula.It determines the adaptive allocation of cloud communication resources,introduces an objective function to obtain the optimal solution after allocation,and completes the adaptive allocation process.The experimental results demonstrate that,with the application of the proposed method,the maximum utilization of user communication resources reaches approximately 99%.The balance coefficient curve approaches 1,and the allocation time remains under 2 s.This indicates that the proposed method has higher adaptive allocation efficiency.展开更多
This paper is aimed at detecting the neutron spectrum of^(241)Am–Be, a widely used neutron source, with the SP9 ~3He proportional counter, which is a multi-sphere spectrometer system of eight thermal neutron detector...This paper is aimed at detecting the neutron spectrum of^(241)Am–Be, a widely used neutron source, with the SP9 ~3He proportional counter, which is a multi-sphere spectrometer system of eight thermal neutron detectors embedded in eight polyethylene(PE) spheres of varying diameters. The transport processes of a neutron in the multi-sphere spectrometer are simulated using the Geant4 code. Two sets of response functions of the PE spheres are obtained for calculating the^(241)Am–Be neutron spectrum.Response Function 1 utilizes the thermal neutron scattering model G4 Neutron HPThermal Scattering for neutron energies of ≤4 eV, and Response Function 2 has no thermal treatment. Neutron spectra of an^(241)Am–Be neutron source are measured and compared to those calculated by using the response functions. The results show that response function with thermal treatment is more accurate and closer to the real spectrum.展开更多
Structural and electronic properties of bimetallic clusters AlnCom with n=1~7 and m=1~2 have been investigated using the B3LYP-DFT method.Structural optimization and frequency analysis were performed at the CEP-121G...Structural and electronic properties of bimetallic clusters AlnCom with n=1~7 and m=1~2 have been investigated using the B3LYP-DFT method.Structural optimization and frequency analysis were performed at the CEP-121G level.The charge-induced structural changes in these anions were discussed.In addition,the corresponding total energies,binding energies,adiabatic electron affinities and vertical electron affinity were also presented and discussed.Our predicted vertical ionization potentials are in reasonable agreement with the experimental ionization potentials.Among different AlnCom and AlnCom-anions (n=1~7,m=1~2),Al4Co,Al6Co,Al4Co-,Al6Co-and Al4Co2-are predicted to be species with high stabilities.展开更多
Network slicing is one of the most important features in 5G which enables a large variety of services with diverse performance requirements by network virtualization. Traditionally, the network can be viewed as a one-...Network slicing is one of the most important features in 5G which enables a large variety of services with diverse performance requirements by network virtualization. Traditionally, the network can be viewed as a one-size-fits-all slice and its services are bundled with proprietary hardware supported by telecom equipment providers. Now with the network virtualization technology in 5G, open networking software can be deployed flexibly on commodity hardware to offer a multi-slice network where each slice can offer a different set of network services. In this research, we propose a multi-slice 5G core architecture by provisioning its User Plane Functions (UPFs) with different QoS requirements. We compare the performance of such a multi-slice system with that of one-size-fits-all single slice architecture under the same resource assignment. Our research objective is to compare the performance of a network slicing architecture with that of a “one-size-fits-all” architecture and validate that the former can achieve better performance with the same underlying infrastructure. The results validate that our proposed system can achieve better performance by slicing one UPF into three with proper resource allocation.展开更多
Membrane technology has been used for H_2 purification. In this paper, the systematic density functional simulations are conducted to study the separation of H_2 from the impurity gases(H_2, N_2, H_2 O, CO, Cl_2, and ...Membrane technology has been used for H_2 purification. In this paper, the systematic density functional simulations are conducted to study the separation of H_2 from the impurity gases(H_2, N_2, H_2 O, CO, Cl_2, and CH_4) by the bilayer porous graphitic carbon nitride(g-C_3 N_4) membrane. Theoretically, the bilayer g-C3 N4 membrane with a diameter of about3.25 A? should be a perfect candidate for H_2 purification from these mixed gases, which is verified by the high selectivity(S) for H_2 over other kinds of gases(3.43 × 1028 for H_2/N2; 1.40 × 1028 for H_262/H_2 O; 1.60 × 10 for H_2/CO; 4.30 × 10^(14) for H_2/Cl_2; 2.50 × 10^(55) for H_2/CH_4), and the permeance(P) of H_2(13 mol/m^2·s·Pa) across the bilayer g-C_3 N_4 membrane at 300 K, which should be of great potential in energy and environmental research. Our studies highlight a new approach towards the final goal of high P and high S molecular-sieving membranes used in simple structural engineering.展开更多
By combining the classical appropriate functions “1, x, x 2” with the method of multiplier enlargement, this paper establishes a theorem to approximate any unbounded continuous functions with modified positive...By combining the classical appropriate functions “1, x, x 2” with the method of multiplier enlargement, this paper establishes a theorem to approximate any unbounded continuous functions with modified positive linear operators. As an example, Hermite Fejér interpolation polynomial operators are analysed and studied, and a general conclusion is obtained.展开更多
In this paper, we establish the following limiting weak-type behaviors of Littlewood-Paley g-function g_φ: for nonnegative function f∈ L^1(R^n),■and ■where f_t(x) =t^(-n)f(t^(-1) x) for t > 0. Meanwhile, the co...In this paper, we establish the following limiting weak-type behaviors of Littlewood-Paley g-function g_φ: for nonnegative function f∈ L^1(R^n),■and ■where f_t(x) =t^(-n)f(t^(-1) x) for t > 0. Meanwhile, the corresponding results for Marcinkiewicz integral and its fractional version with kernels satisfying L_α~q-Dini condition are also given.展开更多
Since the room-temperature detector CdZnTe(CZT) has advantages in terms of detection efficiency,energy resolution, and size, it has been extensively used to detect X-rays and gamma-rays. So far, nuclear radiation dete...Since the room-temperature detector CdZnTe(CZT) has advantages in terms of detection efficiency,energy resolution, and size, it has been extensively used to detect X-rays and gamma-rays. So far, nuclear radiation detectors such as cerium chloride doped with lanthanum bromide(LaBr_3(Ce)), thallium doped with cesium iodide(sI(Tl)), thallium doped with sodium iodide(NaI(Tl)),and high-purity germanium(HPGe) primarily use the spectroscopy-dose rate function(G(E)) to achieve the accurate measurement of air kerma rate(K_a) and ambient dose equivalent rate(H*(10)). However, the spectroscopy-dose rate function has been rarely measured for a CZT detector. In this study, we performed spectrum measurement using a hemispherical CZT detector in a radiation protection standards laboratory. The spectroscopy-dose rate function G(E) of the CZT detector was calculated using the least-squares method combined with the standard dose rate at the measurement position. The results showed that the hemispherical CZT detector could complete the measurement of air kerma rate(K_a) and ambient dose equivalent rate(H*(10)) by using the G(E) function at energies between 48 keV and 1.25 MeV, and the relative intrinsic errors were, respectively, controlled within ± 2. 3 and ± 2. 1%.展开更多
Magnesium(Mg) is crucial for the function of G proteins which play important roles in mediating the inotropic effects of β adrenergic agonists in the heart and are alteredin heart failure.This study was performed to ...Magnesium(Mg) is crucial for the function of G proteins which play important roles in mediating the inotropic effects of β adrenergic agonists in the heart and are alteredin heart failure.This study was performed to determine whether or not dietary Mg deficiency alters functional activity and levels of the two major ventricular G proteins, Gia and Gsa in the heart after myocardial infarction(MI).Six week old rats were fed a Mg adequate or deficient diet for 6 weeks.At the end of week 3,MI was induced by coronary artery ligation.A sham operation was performed as control.After surgery,surviving animals were maintained on their assigned diets for another 3 weeks.Then,cardiac function was measured.Severe hypomagnesemia and increased plasma catecholamine level were observed in all animals fed the Mg deficient diet.A significant reduction of ruyocardial Mg concentration accompanied by elevated plasma and myocardial calcium concentrations was observed in MI animals with existing Mg deficiency vs.animals fed the Mg adequate diet.Cardiac function was impaired in MI rats and further reduced in MI rats with existing Mg deficiency. Gia level was not altered by either Mg deficiency or MI alone,but was dramatically elevated in animals with combined Mg deficiency and MI (9. 9±0.7 arbitrary unit.mg-1 protein) as compared to MI alone (5.8±0. 6,P<0.05 )and Mg deficiency alone(6.1± 0.8,P<0.05 ). Gsa level did not differ between groups.Bacal,GppNHp-and forskolin-but not fluoride-, stimulated adenylyl cyclase activity was signifcantly reduced in MI animals with existing Mg deficiency indicating increased functional activity of Gia.The findings suggest that dietary Mg deficiency increases the expression and functional ac tivity of Gia in the heart after MI, while levels and function of Gsa are not compromised during dietary Mg deficiency either with or without MI.展开更多
Changes in the functional activity and levels of Gsa and Gia in heart failure have been studied predominantly in the end-stage failing heart.The objective of this study was to determine if levels and function of Gsa a...Changes in the functional activity and levels of Gsa and Gia in heart failure have been studied predominantly in the end-stage failing heart.The objective of this study was to determine if levels and function of Gsa and Gia2 in rat hearts change over time following acute myocar(lial infarction (MI) and if so,whether the changes in G proteins are associated with changes in heart function.As compared with sham-operated controls, Giα2, level of MI rats did not change at day l,increased by 64% at day 3 (P<0.01) and 55% at day 9 (P< 0.05)accompanied by reduced adenylyl cyclase activity,and returned to control by day 21. By contrast,Gsa level did not change at any time. Cardiac function in MI animals was markedly impaired at days 1,3 and 9 as evidenced by substantial elevation in LVEDP and reduction in +and -dp/dtmax,and partially restored at day 21. The increased Gia2level in MI rats at days 3 and 9 correlated positively to LVEDP(P< 0.05), and negatively to +and -dp/dtmax (p < 0. 01).The results show a three phase dynamic pattern in Gia2 level following acute MI:a lag phase, an increased expression phase associated with marked impairment of heart function,and a late phase in which the expression retums to control level accompanied by partially restored cardlac function.The results suggest that ② in G protein-mediated pathways,cardiac myocytes respond to MI Via regulating the gene expression of the inhibitory pathway, and ② up-regulation of Gia2 levels is related to the severity of impairment in cardiac function.展开更多
In this paper a generalized tanh-function type method is proposed by using the idea of the transformed rational function method. We show that the (G'/G)?-expansion method is a special case of the generalized tanh-...In this paper a generalized tanh-function type method is proposed by using the idea of the transformed rational function method. We show that the (G'/G)?-expansion method is a special case of the generalized tanh-function type method, so the (G'/G)?-expansion method is considered as a special deformation application of the transformed rational function method. We demonstrate that all solutions obtained by the (G'/G)?-expansion method were found by the generalized tanh-function type method. As applications, we consider mKdV equation. Compared with the (G'/G) -expansion method, the generalized tanh-function type method gives new and more abundant solutions.展开更多
We have previously found that long-term effects of exposure to radiofrequency electromagnetic fields in 5xFAD mice with severe late-stage Alzheimer’s disease reduced both amyloid-βdeposition and glial activation,inc...We have previously found that long-term effects of exposure to radiofrequency electromagnetic fields in 5xFAD mice with severe late-stage Alzheimer’s disease reduced both amyloid-βdeposition and glial activation,including microglia.To examine whether this therapeutic effect is due to the regulation of activated microglia,we analyzed mic roglial gene expression profiles and the existence of microglia in the brain in this study.5xFAD mice at the age of 1.5 months were assigned to sham-and radiofrequency electromagnetic fields-exposed groups and then animals were exposed to 1950 MHz radiofrequency electromagnetic fields at a specific absorption rate of 5 W/kg for 2 hours/day and 5 days/week for 6 months.We conducted behavioral tests including the object recognition and Y-maze tests and molecular and histopathological analysis of amyloid precursor protein/a myloid-beta metabolism in brain tissue.We confirmed that radiofrequency electromagnetic field exposure for 6 months ameliorated cognitive impairment and amyloid-βdeposition.The expression levels of Iba1(pan-microglial marker)and colony-stimulating factor 1 receptor(CSF1R;regulates microglial prolife ration)in the hippocampus in 5xFAD mice treated with radiofrequency electromagnetic fields were significantly reduced compared with those of the sham-exposed group.Subsequently,we analyzed the expression levels of genes related to mic rogliosis and microglial function in the radiofrequency electromagnetic fields-exposed group compared to those of a CSF1R inhibitor(PLX3397)-treated group.Both radiofrequency electromagnetic fields and PLX3397 suppressed the levels of genes related to microgliosis(Csf1r,CD68,and Ccl6)and pro-inflammatory cytokine interleukin-1β.N otably,the expression levels of genes related to mic roglial function,including Trem2,Fcgr1α,Ctss,and Spi1,were decreased after long-term radiofrequency electromagnetic field exposure,which was also observed in response to microglial suppression by PLX3397.These results showed that radiofrequency electromagnetic fields ameliorated amyloid-βpathology and cognitive impairment by suppressing amyloid-βdeposition-induced microgliosis and their key regulator,CSF1R.展开更多
基金funding by Comunidad de Madrid within the framework of the Multiannual Agreement with Universidad Politécnica de Madrid to encourage research by young doctors(PRINCE project).
文摘Future 6G communications are envisioned to enable a large catalogue of pioneering applications.These will range from networked Cyber-Physical Systems to edge computing devices,establishing real-time feedback control loops critical for managing Industry 5.0 deployments,digital agriculture systems,and essential infrastructures.The provision of extensive machine-type communications through 6G will render many of these innovative systems autonomous and unsupervised.While full automation will enhance industrial efficiency significantly,it concurrently introduces new cyber risks and vulnerabilities.In particular,unattended systems are highly susceptible to trust issues:malicious nodes and false information can be easily introduced into control loops.Additionally,Denialof-Service attacks can be executed by inundating the network with valueless noise.Current anomaly detection schemes require the entire transformation of the control software to integrate new steps and can only mitigate anomalies that conform to predefined mathematical models.Solutions based on an exhaustive data collection to detect anomalies are precise but extremely slow.Standard models,with their limited understanding of mobile networks,can achieve precision rates no higher than 75%.Therefore,more general and transversal protection mechanisms are needed to detect malicious behaviors transparently.This paper introduces a probabilistic trust model and control algorithm designed to address this gap.The model determines the probability of any node to be trustworthy.Communication channels are pruned for those nodes whose probability is below a given threshold.The trust control algorithmcomprises three primary phases,which feed themodel with three different probabilities,which are weighted and combined.Initially,anomalous nodes are identified using Gaussian mixture models and clustering technologies.Next,traffic patterns are studied using digital Bessel functions and the functional scalar product.Finally,the information coherence and content are analyzed.The noise content and abnormal information sequences are detected using a Volterra filter and a bank of Finite Impulse Response filters.An experimental validation based on simulation tools and environments was carried out.Results show the proposed solution can successfully detect up to 92%of malicious data injection attacks.
文摘AIM: To investigate the relationship between gastric dysmotility,gastrointestinal hormone abnormalities, and neuroendocrine cells in gastrointestinal mucosa in patients with functional dyspepsia (FD).METHODS: Gastric emptying was assessed with solid radiopaque markers in 54 FD patients, and the patients were divided into two groups according to the results, one with delayed gastric emptying and the other with normal gastric emptying. Seventeen healthy volunteers acted as normal controls. Fasting and postprandial plasma levels and gastroduodenal mucosal levels of gastrointestinal hormones gastrin, somatostatin (SS) and neurotensin (NT)were measured by radioimmunoassay in all the subjects.G cells (gastrin-producing cells) and D cells (SS-producing cells) in gastric antral mucosa were immunostained with rabbit anti-gastrin polyclonal antibody and rabbit anti-SS polyclonal antibody, respectively, and analyzed quantitatively by computerized image analysis.RESULTS: The postprandial plasma gastrin levels, the fasting and postprandial plasma levels and the gastric and duodenal mucosal levels of NT were significantly higher in the FD patients with delayed gastric emptying than in those with normal gastric emptying and normal controls. The number and gray value of G and D cells and the G cell/D cell number ratio did not differ significantly between normal controls and the FD patients with or without delayed gastric emptying.CONCLUSION: Our findings suggest that the abnormalities of gastrin and NT may play a role in the pathophysiology of gastric dysmotility in FD patients, and the abnormality of postprandial plasma gastrin levels in FD patients with delayed gastric emptying is not related to the changes both in the number and gray value of G cells and in the G cell/D cell number ratio in gastric antral mucosa.
基金The project supported by National Natural Science Foundation of China under Grant No. 40390150 and the International Collaboration Research Team Program of the Chinese Academy of Sciences
文摘Non-Maxwellian particle distribution functions possessing high energy tail and shoulder in the profile of distribution function considerably change the damping characteristics of the waves. In the present paper Landau damping of electron plasma (Langmuir) waves and ion-acoustic waves in a hot, isotropic, unmagnetized plasma is studied with the generalized (r, q) distribution function. The results show that for the Langmuir oscillations Landau damping becomes severe as the spectral index r or q reduces. However, for the ion-acoustic waves Landau damping is more sensitive to the ion temperature than the spectral indices.
基金supported by the Ministry of Science and Technology (2012CB214900 and 2011CB808504)the National Science Foundation of China (21133007)
文摘Equilibrium structures and infrared spectra of four typical molecular models of coal have been studied by density functional calculations. Combining theoretical calculations on the coal models with experimental FT-IR spectra of selected low rank perhydrous coals, a plausible molecular representation for this kind of coals was proposed, and its predicted IR spectra reasonably match the experimental observation. Calculations indicate that the cleavage of the C-C bridge bond for the coal structures considered here occurs at about 540 ℃ and the C-O ether bridge bond may break under temperature ranging from 500 to 600 ℃for the aryl-CH2-O-CH2-aryl ether bond or from 200 to 300 ℃ for the aryl-CH2-O-aryl ether bond, showing remarkable effect of the local structural environment. The coal model containing the carboxyl group may release CO2 at about 300 ℃ through the decarboxylation with a barrier of 69 kcal/mol.
基金This research was supported by Science and Technology Research Project of Education Department of Jiangxi Province,China(Nos.GJJ2206701,GJJ2206717).
文摘The current resource allocation in 5G vehicular networks for mobile cloud communication faces several challenges,such as low user utilization,unbalanced resource allocation,and extended adaptive allocation time.We propose an adaptive allocation algorithm for mobile cloud communication resources in 5G vehicular networks to address these issues.This study analyzes the components of the 5G vehicular network architecture to determine the performance of different components.It is ascertained that the communication modes in 5G vehicular networks for mobile cloud communication include in-band and out-of-band modes.Furthermore,this study analyzes the single-hop and multi-hop modes in mobile cloud communication and calculates the resource transmission rate and bandwidth in different communication modes.The study also determines the scenario of one-way and two-way vehicle lane cloud communication network connectivity,calculates the probability of vehicle network connectivity under different mobile cloud communication radii,and determines the amount of cloud communication resources required by vehicles in different lane scenarios.Based on the communication status of users in 5G vehicular networks,this study calculates the bandwidth and transmission rate of the allocated channels using Shannon’s formula.It determines the adaptive allocation of cloud communication resources,introduces an objective function to obtain the optimal solution after allocation,and completes the adaptive allocation process.The experimental results demonstrate that,with the application of the proposed method,the maximum utilization of user communication resources reaches approximately 99%.The balance coefficient curve approaches 1,and the allocation time remains under 2 s.This indicates that the proposed method has higher adaptive allocation efficiency.
基金supported by ITER Plan National Major Project(No.2008GB109000)the Introduces Talents Scientific Research Project of Guizhou University(2014,No.32)
文摘This paper is aimed at detecting the neutron spectrum of^(241)Am–Be, a widely used neutron source, with the SP9 ~3He proportional counter, which is a multi-sphere spectrometer system of eight thermal neutron detectors embedded in eight polyethylene(PE) spheres of varying diameters. The transport processes of a neutron in the multi-sphere spectrometer are simulated using the Geant4 code. Two sets of response functions of the PE spheres are obtained for calculating the^(241)Am–Be neutron spectrum.Response Function 1 utilizes the thermal neutron scattering model G4 Neutron HPThermal Scattering for neutron energies of ≤4 eV, and Response Function 2 has no thermal treatment. Neutron spectra of an^(241)Am–Be neutron source are measured and compared to those calculated by using the response functions. The results show that response function with thermal treatment is more accurate and closer to the real spectrum.
基金supported by the National Natural Science Foundation of China (20603021)Youth Foundation of Shanxi Province (2007021009)
文摘Structural and electronic properties of bimetallic clusters AlnCom with n=1~7 and m=1~2 have been investigated using the B3LYP-DFT method.Structural optimization and frequency analysis were performed at the CEP-121G level.The charge-induced structural changes in these anions were discussed.In addition,the corresponding total energies,binding energies,adiabatic electron affinities and vertical electron affinity were also presented and discussed.Our predicted vertical ionization potentials are in reasonable agreement with the experimental ionization potentials.Among different AlnCom and AlnCom-anions (n=1~7,m=1~2),Al4Co,Al6Co,Al4Co-,Al6Co-and Al4Co2-are predicted to be species with high stabilities.
文摘Network slicing is one of the most important features in 5G which enables a large variety of services with diverse performance requirements by network virtualization. Traditionally, the network can be viewed as a one-size-fits-all slice and its services are bundled with proprietary hardware supported by telecom equipment providers. Now with the network virtualization technology in 5G, open networking software can be deployed flexibly on commodity hardware to offer a multi-slice network where each slice can offer a different set of network services. In this research, we propose a multi-slice 5G core architecture by provisioning its User Plane Functions (UPFs) with different QoS requirements. We compare the performance of such a multi-slice system with that of one-size-fits-all single slice architecture under the same resource assignment. Our research objective is to compare the performance of a network slicing architecture with that of a “one-size-fits-all” architecture and validate that the former can achieve better performance with the same underlying infrastructure. The results validate that our proposed system can achieve better performance by slicing one UPF into three with proper resource allocation.
基金Project supported by the Fundamental Research Funds for the Central Universities,China(Grant No.2018B19414)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20161501)+5 种基金the Six Talent Peaks Project in Jiangsu Province,China(Grant No.2015-XCL-010)the National Natural Science Foundation of China(Grant Nos.51776094 and 51406075)the Program of Henan Provincial Department of Education,China(Grant No.16A330004)the Special Fund of Nanyang Normal University,China(Grant No.ZX2016003)the Science and Technology Program of Henan Department of Science and Technology,China(Grant No.182102310609)the Scientific Research and Service Platform Fund of Henan Province,China(Grant No.2016151)
文摘Membrane technology has been used for H_2 purification. In this paper, the systematic density functional simulations are conducted to study the separation of H_2 from the impurity gases(H_2, N_2, H_2 O, CO, Cl_2, and CH_4) by the bilayer porous graphitic carbon nitride(g-C_3 N_4) membrane. Theoretically, the bilayer g-C3 N4 membrane with a diameter of about3.25 A? should be a perfect candidate for H_2 purification from these mixed gases, which is verified by the high selectivity(S) for H_2 over other kinds of gases(3.43 × 1028 for H_2/N2; 1.40 × 1028 for H_262/H_2 O; 1.60 × 10 for H_2/CO; 4.30 × 10^(14) for H_2/Cl_2; 2.50 × 10^(55) for H_2/CH_4), and the permeance(P) of H_2(13 mol/m^2·s·Pa) across the bilayer g-C_3 N_4 membrane at 300 K, which should be of great potential in energy and environmental research. Our studies highlight a new approach towards the final goal of high P and high S molecular-sieving membranes used in simple structural engineering.
文摘By combining the classical appropriate functions “1, x, x 2” with the method of multiplier enlargement, this paper establishes a theorem to approximate any unbounded continuous functions with modified positive linear operators. As an example, Hermite Fejér interpolation polynomial operators are analysed and studied, and a general conclusion is obtained.
文摘In this paper, we establish the following limiting weak-type behaviors of Littlewood-Paley g-function g_φ: for nonnegative function f∈ L^1(R^n),■and ■where f_t(x) =t^(-n)f(t^(-1) x) for t > 0. Meanwhile, the corresponding results for Marcinkiewicz integral and its fractional version with kernels satisfying L_α~q-Dini condition are also given.
基金supported by the National Key Scientific Instruments to Develop Dedicated(Nos.2013YQ090811 and 2016YFF0103800)
文摘Since the room-temperature detector CdZnTe(CZT) has advantages in terms of detection efficiency,energy resolution, and size, it has been extensively used to detect X-rays and gamma-rays. So far, nuclear radiation detectors such as cerium chloride doped with lanthanum bromide(LaBr_3(Ce)), thallium doped with cesium iodide(sI(Tl)), thallium doped with sodium iodide(NaI(Tl)),and high-purity germanium(HPGe) primarily use the spectroscopy-dose rate function(G(E)) to achieve the accurate measurement of air kerma rate(K_a) and ambient dose equivalent rate(H*(10)). However, the spectroscopy-dose rate function has been rarely measured for a CZT detector. In this study, we performed spectrum measurement using a hemispherical CZT detector in a radiation protection standards laboratory. The spectroscopy-dose rate function G(E) of the CZT detector was calculated using the least-squares method combined with the standard dose rate at the measurement position. The results showed that the hemispherical CZT detector could complete the measurement of air kerma rate(K_a) and ambient dose equivalent rate(H*(10)) by using the G(E) function at energies between 48 keV and 1.25 MeV, and the relative intrinsic errors were, respectively, controlled within ± 2. 3 and ± 2. 1%.
文摘Magnesium(Mg) is crucial for the function of G proteins which play important roles in mediating the inotropic effects of β adrenergic agonists in the heart and are alteredin heart failure.This study was performed to determine whether or not dietary Mg deficiency alters functional activity and levels of the two major ventricular G proteins, Gia and Gsa in the heart after myocardial infarction(MI).Six week old rats were fed a Mg adequate or deficient diet for 6 weeks.At the end of week 3,MI was induced by coronary artery ligation.A sham operation was performed as control.After surgery,surviving animals were maintained on their assigned diets for another 3 weeks.Then,cardiac function was measured.Severe hypomagnesemia and increased plasma catecholamine level were observed in all animals fed the Mg deficient diet.A significant reduction of ruyocardial Mg concentration accompanied by elevated plasma and myocardial calcium concentrations was observed in MI animals with existing Mg deficiency vs.animals fed the Mg adequate diet.Cardiac function was impaired in MI rats and further reduced in MI rats with existing Mg deficiency. Gia level was not altered by either Mg deficiency or MI alone,but was dramatically elevated in animals with combined Mg deficiency and MI (9. 9±0.7 arbitrary unit.mg-1 protein) as compared to MI alone (5.8±0. 6,P<0.05 )and Mg deficiency alone(6.1± 0.8,P<0.05 ). Gsa level did not differ between groups.Bacal,GppNHp-and forskolin-but not fluoride-, stimulated adenylyl cyclase activity was signifcantly reduced in MI animals with existing Mg deficiency indicating increased functional activity of Gia.The findings suggest that dietary Mg deficiency increases the expression and functional ac tivity of Gia in the heart after MI, while levels and function of Gsa are not compromised during dietary Mg deficiency either with or without MI.
文摘Changes in the functional activity and levels of Gsa and Gia in heart failure have been studied predominantly in the end-stage failing heart.The objective of this study was to determine if levels and function of Gsa and Gia2 in rat hearts change over time following acute myocar(lial infarction (MI) and if so,whether the changes in G proteins are associated with changes in heart function.As compared with sham-operated controls, Giα2, level of MI rats did not change at day l,increased by 64% at day 3 (P<0.01) and 55% at day 9 (P< 0.05)accompanied by reduced adenylyl cyclase activity,and returned to control by day 21. By contrast,Gsa level did not change at any time. Cardiac function in MI animals was markedly impaired at days 1,3 and 9 as evidenced by substantial elevation in LVEDP and reduction in +and -dp/dtmax,and partially restored at day 21. The increased Gia2level in MI rats at days 3 and 9 correlated positively to LVEDP(P< 0.05), and negatively to +and -dp/dtmax (p < 0. 01).The results show a three phase dynamic pattern in Gia2 level following acute MI:a lag phase, an increased expression phase associated with marked impairment of heart function,and a late phase in which the expression retums to control level accompanied by partially restored cardlac function.The results suggest that ② in G protein-mediated pathways,cardiac myocytes respond to MI Via regulating the gene expression of the inhibitory pathway, and ② up-regulation of Gia2 levels is related to the severity of impairment in cardiac function.
文摘In this paper a generalized tanh-function type method is proposed by using the idea of the transformed rational function method. We show that the (G'/G)?-expansion method is a special case of the generalized tanh-function type method, so the (G'/G)?-expansion method is considered as a special deformation application of the transformed rational function method. We demonstrate that all solutions obtained by the (G'/G)?-expansion method were found by the generalized tanh-function type method. As applications, we consider mKdV equation. Compared with the (G'/G) -expansion method, the generalized tanh-function type method gives new and more abundant solutions.
基金Institute of Information&Communications Technology Planning&Evaluation(IITP)grant funded by Korea government(MSIT),Nos.2017-0-00961 and 2019-0-00102(to HDC)。
文摘We have previously found that long-term effects of exposure to radiofrequency electromagnetic fields in 5xFAD mice with severe late-stage Alzheimer’s disease reduced both amyloid-βdeposition and glial activation,including microglia.To examine whether this therapeutic effect is due to the regulation of activated microglia,we analyzed mic roglial gene expression profiles and the existence of microglia in the brain in this study.5xFAD mice at the age of 1.5 months were assigned to sham-and radiofrequency electromagnetic fields-exposed groups and then animals were exposed to 1950 MHz radiofrequency electromagnetic fields at a specific absorption rate of 5 W/kg for 2 hours/day and 5 days/week for 6 months.We conducted behavioral tests including the object recognition and Y-maze tests and molecular and histopathological analysis of amyloid precursor protein/a myloid-beta metabolism in brain tissue.We confirmed that radiofrequency electromagnetic field exposure for 6 months ameliorated cognitive impairment and amyloid-βdeposition.The expression levels of Iba1(pan-microglial marker)and colony-stimulating factor 1 receptor(CSF1R;regulates microglial prolife ration)in the hippocampus in 5xFAD mice treated with radiofrequency electromagnetic fields were significantly reduced compared with those of the sham-exposed group.Subsequently,we analyzed the expression levels of genes related to mic rogliosis and microglial function in the radiofrequency electromagnetic fields-exposed group compared to those of a CSF1R inhibitor(PLX3397)-treated group.Both radiofrequency electromagnetic fields and PLX3397 suppressed the levels of genes related to microgliosis(Csf1r,CD68,and Ccl6)and pro-inflammatory cytokine interleukin-1β.N otably,the expression levels of genes related to mic roglial function,including Trem2,Fcgr1α,Ctss,and Spi1,were decreased after long-term radiofrequency electromagnetic field exposure,which was also observed in response to microglial suppression by PLX3397.These results showed that radiofrequency electromagnetic fields ameliorated amyloid-βpathology and cognitive impairment by suppressing amyloid-βdeposition-induced microgliosis and their key regulator,CSF1R.