Research and Practice of Cooperative Teaching System for Software Engineering Major

In order to respond to the new engineering construction of the Ministry of Education,and explore the innovative talent training model of collaborative education and multidisciplinary integration,this paper relies on the software engineering teaching team of the School of Software Engineering,Beijing University of Posts and Telecommunications,through the implementation of the collaborative education project of the Ministry of Education,and proposes the multi-course collaborative practice teaching system,through the reasonable cross-fusion of the practical links of the 5 software engineering courses in the college,realizes the multi-course collaborative education and reasonable cross-fusion of courses,shares practical project resources,introduces new enterprise technologies,and guides students’innovation and entrepreneurship provide a meaningful reference for the collaborative arrangement of teaching content and cross-disciplinary integration in the current university education system.

Synthesis and photoluminescence properties of Nd_2O_3 nanoparticles modified by sodium bis(2-ethylhexyl) sulfosuccinate

This paper reports that Nd2O3 nanoparticles modified by AOT（sodium bis（2-ethylhexyl） sulfosuccinate） were prepared using microemulsion method in the system of water and propanol/AOT/toluene. Transmission electron microscopy shows that the Nd2O3 nanoparticles take the shape of sphere with 18 nm and 31 nm with different preparation. The organic sol of Nd2O3 nanoparticles is very stable at room temperature. X-ray diffraction results show that the product has hexagonal phase structure. Two ultraviolet emission band at 344 nm and 361 nm corresponding to the transition of ^4 D3/2→4 I9/2 and 2P3/2→^4I 11/2 or ^4D 3/2→ ^4 I 13/2 were observed.

Photoionization Cross Section and Resonance Structure of Mn＋

Mn~+ 的光电游离十字节计算为从 48 eV 到 56 eV 的光子精力在许多身体不安理论的形式主义被执行。从 3p， 3d，和 4s 支壳层的 Weconsider 刺激。当对总数的反响的贡献穿过节，强壮的 3p → 3d 和 3p → 4 s 转变的效果被包括。对实验的好同意被发现。

Influence of Strain-Reducing Layer on Strain Distribution of Self-Organized InAs/GaAs Quantum Dot and Redshift of Photoluminescence Wavelength

A systematic investigation about the strain distributions around the InAs/GaAs quantum dots using the finite element method is presented. A special attention is paid to influence of an Ino.2 Gao.sAs strain reducing layer. The numerical results show that the horizontal- and vertical-strain components and the biaz^ial strain are reinforced in the InAs quantum dot due to the strain-reducing layer. However, the hydrostatic strain in the quantum dot is reduced. In the framework of eight-band k · p theory, we study the band edge modifications due to the presence of a strain reducing layer. The results demonstrate that the strain reducing layer yields the decreasing band gap, i.e., the redshift phenomenon is observed in experiments. Our calculated results show that degree of the redshift will increase with the increasing thickness of the strain-reducing layer. The calculated results can explain the experimental results in the literature, and further confirm that the long wavelength emission used for optical fibre communication is realizable by adjusting the dependent parameters. However, based on the calculated electronic and heavy-hole wave function distributions, we find that the intensity of photoluminescence will exhibits some variations with the increasing thickness of the strain-reducing layer.

A Load-balance and EEDF based strategy for reducing transmission delay of VoIP services in IEEE 802.16e system

To decrease the transmission delay of uplink voice over IP(VoIP)services in IEEE 802.16e sys-tem,a novel strategy which includes a load-balance algorithm and an extended earliest deadline first(EEDF)scheduling algorithm is proposed.Subsequently,this paper analyzes the performance of the pro-posed strategy in terms of transmission delay of VoIP services,system capacity,throughput and compati-bility with IEEE 802 .16e standard.Finally,simulation experiments are carried out to verify the improve-ment of the proposed strategy.The simulation results match well with the theoretical analysis and showthat the proposed strategy reduces the transmission delay of uplink VoIP services and improves the capaci-ty and throughput.These improvements are remarkable especially when the load of system is heavy.

A Secure and Effective Energy-Aware Fixed-Point Quantization Scheme for Asynchronous Federated Learning

Asynchronous federated learning(AsynFL)can effectivelymitigate the impact of heterogeneity of edge nodes on joint training while satisfying participant user privacy protection and data security.However,the frequent exchange of massive data can lead to excess communication overhead between edge and central nodes regardless of whether the federated learning(FL)algorithm uses synchronous or asynchronous aggregation.Therefore,there is an urgent need for a method that can simultaneously take into account device heterogeneity and edge node energy consumption reduction.This paper proposes a novel Fixed-point Asynchronous Federated Learning(FixedAsynFL)algorithm,which could mitigate the resource consumption caused by frequent data communication while alleviating the effect of device heterogeneity.FixedAsynFL uses fixed-point quantization to compress the local and global models in AsynFL.In order to balance energy consumption and learning accuracy,this paper proposed a quantization scale selection mechanism.This paper examines the mathematical relationship between the quantization scale and energy consumption of the computation/communication process in the FixedAsynFL.Based on considering the upper bound of quantization noise,this paper optimizes the quantization scale by minimizing communication and computation consumption.This paper performs pertinent experiments on the MNIST dataset with several edge nodes of different computing efficiency.The results show that the FixedAsynFL algorithm with an 8-bit quantization can significantly reduce the communication data size by 81.3%and save the computation energy in the training phase by 74.9%without significant loss of accuracy.According to the experimental results,we can see that the proposed AsynFixedFL algorithm can effectively solve the problem of device heterogeneity and energy consumption limitation of edge nodes.

Performance Analysis of Optical Transmission Based on Seven Cores Fiber

This essay designed a kind of new seven-core fiber with lower crosstalk and loss,and made space division multiplexing transmission experiment based on this seven-core fiber.It is known that crosstalk has the most serious influence in multicore fiber transmission process.Before the experiment,the affecting factors of fiber crosstalk were analyzed through simulation,such as core space,bending radius,and fiber length.Combined with the simulation analysis,the design scheme of multicore fiber with low crosstalk was obtained.Before the fiber design,various factors of influence crosstalk such as the coreto-core distance,bending radius,fiber length and so on.Based on the simulation analysis,conclusion has made on the design scheme of multi-core optimal fiber with low crosstalk.The space division multiplexing and wavelength division multiplexing technology,was adopted to conduct seven-core optical fiber transmission of 58.7km.The crosstalk of adjacent core was suppressed to as low as 45 d B/km,the attenuation of inner core was 0.24 d B/km,the outer cores' 0.32 d B/km.Different bit error rate(BER) performances were also studied under different conditions,through reasonably designing the system to reduce the error rate,improve the performance of the system,and realize long distance and large capacity transmission with fiber.

Controlled Teleportation of Two-Partic le Entanglement via a Cluster State

In order to teleport an unknown two-particle entangled state via a cluster state,a controlled teleportation scheme is proposed.It is shown that an unknown two-particle entangled state can be successfully transmitted from the sender Alice to the receiver Bob with the help of the supervisor Charlie via the only one four-particle cluster state.The receiver can reconstruct the teleported state according to the measurement results of the sender and supervisor.Quantum Controlled-NOT (CNOT) gate and POVM are used,which have been accomplished in a quantum experiment,so it is believed that this scheme will be realized by experiment.By analysis,the success probability of the proposed scheme reaches 1.0.

Practice Exploration of Blended Teaching Based on Smart Classroom

Facing the information age,college teachers need to innovate teaching methods constantly and realize student-centered teaching reform.This paper takes the“Agile estimation”teaching unit of“Software Project Management”as the research object,and carries out the teaching process design and application of BOPPPS model based on smart classroom according to the teaching purpose and content of the teaching unit.In teaching practice,multi-dimensional blended teaching mode is adopted and a variety of teaching methods are used to realize the teaching loop from online to offline and then to online.The results show that the teaching mode enhances students’learning enthusiasm,enhances students’participation and subjective initiative,and effectively improves the teaching effect of the course.

Performance of Differential-Phase-Shift Keying Protocol Applying 1310 nm Up-Conversion Single-Photon Detector

调音的 differential-phase-shift (DPSK ) 的表演使用 1310 nm 起来变换的协议单个光子的察觉者被分析。错误率和通讯为三个量钥匙分发协议被评为距离的功能，班尼特臂章 1984， Bennett-Brassard-Mermin 1992，和 DPSK，被介绍。然后，我们用 1310nm 起来变换察觉者比较这三个协议的表演。我们得出使用察觉者的 DPSK 协议比另外的二个协议有重要优点的结论。更长的传动距离和更低的误差率能被完成。[从作者抽象]

Modeling of Few-Mode Multi-Core Optical Fiber Channe Based on Non-Uniform Mode Field Distribution

In this paper, the influencing factors that affect few-mode and multi core optical fiber channel are analyzed in a comprehensive way. The theoretical modeling and computer simulation of the information channel are carried out and then the modeling scheme of few-mode multicore optical fiber channel based on non-uniform mode field distribution is put forward. The proposed modeling scheme can not only exponentially increases the system capacity through fewmode multi-core optical fiber channel, but has better transmission performance compared to the channel of the same type to the uniform channel revealing from the simulation results.

Facial Landmark Localization by Gibbs Sampling

In this paper, we introduce a novel method for facial landmark detection. We localize facial landmarks according to the MAP crite rion. Conventional gradient ascent algorithms get stuck at the local optimal solution. Gibbs sampling is a kind of Markov Chain Monte Carlo （MCMC） algorithm. We choose it for optimization because it is easy to implement and it guarantees global conver gence. The posterior distribution is obtained by learning prior distribution and likelihood function. Prior distribution is assumed Gaussian. We use Principle Component Analysis （PCA） to reduce the dimensionality and learn the prior distribution. Local Linear Support Vector Machine （LLSVM） is used to get the likelihood function of every key point. In our experiment, we compare our de tector with some other wellknown methods. The results show that the proposed method is very simple and efficient. It can avoid trapping in local optimal solution.

Teaching Reform on Team-based Innovative Talent Training Model in Computer Software

As a prominent branch of computer science,computer software focuses on technology development and practical application,and it is of great importance in modern social and economic life.Universities need to train postgraduate students that master software engineering to satisfy the needs of high-level talents,preparing for the rapid development of the software industry.Postgraduate is an important stage to cultivate talented students in software engineering.Mentors in relevant majors need to combine advantages of their team while establishing an innovative mode for training talents,mining most potentials of students,and cultivating their ability.We have explored the team-based training mode of computer software major and scientific evaluation methods of innovation ability,shared critical importance in fulfilling fruitions of research,and proposed solutions to real problems especially under the background of“Double First-Class”.This paper decomposes and quantifies the evaluation indicators of the innovation ability of computer software graduate students through literature research and questionnaire surveys.Consequently,we establish a talent evaluation indexing system and build a team-based evaluation system for the innovation ability of graduate student in computer software major.

An Optimal Lifetime Utility Routing for 5G and Energy-Harvesting Wireless Networks

Harvesting energy from environmental sources such as solar and wind can mitigate or solve the limited-energy problem in wireless sensor networks. In this paper, we propose an energy-harvest-aware route-selection method that incorporates harvest availability properties and energy storage capacity limits into the routing decisions. The harvest-aware routing problem is formulated as a lin- ear program with a utility-based objective function that balances the two conflicting routing objectives of maximum total and maxi- mum minimum residual network energy. The simulation results show that doing so achieves a longer network lifetime, defined as the time-to-first-node-death in the network. Additionally, most existing energy-harvesting routing algorithms route each traffic flow independently from each other. The LP formulation allows for a joint optimization of multiple trafic flows. Better residual energy statistics are also achieved by such joint consideration compared to independent optimization of each commodity.

A survey of social network and information dissemination analysis

In recent years,with the rapid growth of social network services(SNS),social networks pervade nearly every aspect of our daily lives.Social networks are influencing today’s societal and cultural issues,and changing the way of people seeing themselves.To fully understand the running mechanisms of social networks,in this paper,we aim at series of high knitted and important elements of online social networks.We mainly focus on 3 important but also open research problems,they are(1)structural properties and evolving laws,(2)social crowds and their interaction behaviors and(3)information and its diffusion.In this paper,we review the related work on the 3 problems.Then,we briefly introduce some interesting research directions and our progress on these research problems.

Privacy Protection with Dynamic Pseudonym-Based Multiple Mix-Zones Over Road Networks

In this research we proposed a strategy for location privacy protection which addresses the issues related with existing location privacy protection techniques. Mix-Zones and pseudonyms are considered as the basic building blocks for location privacy; however, continuously changing pseudonyms process at multiple locations can enhance user privacy. It has been revealed that changing pseudonym at improper time and location may threat to user's privacy. Moreover, certain methods related to pseudonym change have been proposed to attain desirable location privacy and most of these solutions are based upon velocity, GPS position and direction of angle. We analyzed existing methods related to location privacy with mix zones, such as RPCLP, EPCS and MODP, where it has been observed that these methods are not adequate to attain desired level of location privacy and suffered from large number of pseudonym changes. By analyzing limitations of existing methods, we proposed Dynamic Pseudonym based multiple mix zone(DPMM) technique, which ensures highest level of accuracy and privacy. We simulate our data by using SUMO application and analysis results has revealed that DPMM outperformed existing pseudonym change techniques and achieved better results in terms of acquiring high privacy with small number of pseudonym change.

A novel duplex WDM-PON with DPSK modulated downstream and re-modulation of the downlink signal for OOK upstream

We experimentally demonstrate and analyze a 10 Gbit/s full duplex wavelength division multiplexing passive optical network (WDM-PON) system. A non-return-to-zero differential phase shift keying (NRZ-DPSK) modulation technique is first utilized for downlink direction, and then the downlink signal is re-modulated for the uplink direction using intensity modulation technique of on-off keying (OOK) with a data rate of 10 Gbit/s per channel. An effective colorless WDM-PON full duplex transmission system is achieved for the data rate of 10 Gbit/s per channel with a channel spacing of 60 GHz over the distance of 25 km with low power penalty.

Increasing Ranks of Linear Finite Automata and Complexity of FA Public Key Cryptosystem

The encryption algorithm of finite automata (FA) public key cryptosystem is implemented by a weakly invertible finite automata (WIFA) which is composed of a nonlinear WIFA with delay 0 and a linear WIFA with delay τ. In this paper, we proved that such an automaton bears the same properties as the linear WIFA and the increasing ranks of the latter are key factors to affecting the former. A probabilistic algorithm is given to realize a ciphertext attack, and its complexity is analysed through the increasing ranks of the linear WIFA. The size of the parameters for safe linear WIFA is estimated.

Cooperative Interference Game in Cognitive Radio Hidden Terminal Scenario

Hidden terminal problem in spectrum sensing is one of the most challenging problems in cognitive radio network(CRN).To tackle this problem,we propose a novel Cooperative Interference Game scheme in this paper.The scheme adopted full duplex(FD)mode to sense over multiple sub-bands in an iterative manner without extra sensing devices.The implementation algorithm of the proposed scheme is consisted of three modules:the formulation of the maximum transmit power limitation of second user(SU);the self-interference cancellation coefficient;and the optimal location of SU for an optimized low collision probability.Monte Carlo simulation proved that compared with cooperative spectrum sensing,the proposed scheme significantly improves the performance of spectrum detection and mitigates hidden terminal problem to a large extent with less energy consumption.

A USCM Model Driven Approach to Service Design

This paper adopts the USCM (Universal Service Component Model) recommended by Telecommunication Information Networking Architecture Consortium (TINA-C) to design services, which can increase service consistency and facilitate service management. Furthermore the unification of structure organization of services can be achieved whether the service is large or small, or complex or simple. This provides great reusability for service design. Inaddition, the problem how service management can be an integrated part of service driven by USCM model is dissussed.