The total cross sections of the ^(11)B(α,n)^(14N) and the ^(10)B(α,n)^(13)N reactions between 2 and 6 MeV

There is considerable interest in potential aneutronic fusion reactors. One possible reaction is^(11)B(p,a)2a.However, the emitted alpha particles are energetic enough to generate neutrons by interacting with boron inside the reactor through the ^(11)B(α,n)^(14N) and ^(10)B(α,n)^(13)N reactions.To aid in evaluating neutron production within this potential aneutronic reactor, the total cross sections were measured for the ^(11)B(α,n)^(14N) reaction between 2 and 6 MeV and for the ^(10)B(α,n)^(13)N reaction between 2 and 4.8 MeV. The results are presented and compared with previously reported results.

Generating routes for autonomous driving in vehicle-to-infrastructure communications

The study of vehicular networks has attracted considerable interest in academia and the industry.In the broad area,connected vehicles and autonomous driving are technologies based on wireless data communication between vehicles or between vehicles and infrastructures.A Vehicle-to-Infrastructure(V2I)system consists of communications and computing over vehicles and related infrastructures.In such a system,wireless sensors are installed in some selected points along roads or driving areas.In autonomous driving,it is crucial for a vehicle to figure out the ideal routes by the communications between its equipped sensors and infrastructures then the vehicle is automatically moving along the routes.In this paper,we propose a Bezier curve based recursive algorithm,which effectively creates routes for vehicles through the communication between the On-Board Unit(OBU)and the Road-Side Units(RSUs).In addition,this approach generates a very low overhead.We conduct simulations to test the proposed algorithm in various situations.The experiment results demonstrate that our algorithm creates almost ideal routes.

An ellipse-guided routing algorithm in wireless sensor networks

In wireless sensor networks,sensor nodes are deployed to collect data,perform calculations,and forward information to either other nodes or sink nodes.Recently,geographic routing has become extremely popular because it only requires the locations of sensor nodes and is very efficient.However,the local minimum phenomenon,which hinders greedy forwarding,is a major problem in geographic routing.This phenomenon is attributed to an area called a hole that lacks active sensors,which either prevents the packet from being forwarded to a destination node or produces a long detour path.In order to solve the hole problem,mechanisms to detect holes and determine landmark nodes have been proposed.Based on the proposed mechanisms,landmark-based routing was developed in which the source node first sends a packet to the landmark node,and the landmark node then sends the packet to the destination.However,this approach often creates a constant node sequence,causing nodes that perform routing tasks to quickly run out of energy,thus producing larger holes.In this paper,a new approach is proposed in which two virtual ellipses are created with the source,landmark,and destination nodes.Then guide the forwarding along the virtual ellipses.Furthermore,a recursive algorithm is designed to ensure a shortcut even if there are multiple holes or a hole has multiple landmarks.Thus,the proposed approach improves both geographic routing and energy efficiency routing.Simulation experiments show that the proposed approach increases the battery life of sensor nodes,lowers the end-to-end delay,and generates a short path.

Paraspinal Muscle Segmentation in CT Images Using GSM-Based Fuzzy C-Means Clustering

Minimally Invasive Spine surgery (MISS) was developed to treat disorders of the spine with less disruption to the muscles. Surgeons use CT images to monitor the volume of muscles after operation in order to evaluate the progress of patient recovery. The first step in the task is to segment the muscle regions from other tissues/organs in CT images. However, manual segmentation of muscle regions is not only inaccurate, but also time consuming. In this work, Gray Space Map (GSM) is used in fuzzy c-means clustering algorithm to segment muscle regions in CT images. GSM com- bines both spatial and intensity information of pixels. Experiments show that the proposed GSM- based fuzzy c-means clustering muscle CT image segmentation yields very good results.

当前中美线上中文教学研训活动项目的知识技能布局

新冠疫情使得许多传统的国际汉语教学研训活动不得不改为线上,许多教师专业成长学术机构在全球中文教师专业发展方面做出了巨大努力,举办了大量研讨培训活动,这些活动极大地突破了地域限制,使得全球的中文教师因此受益。但鉴于主、客观原因,活动设计缺乏协调和默契,总体布局是否合理需要探明。本研究汇总了疫情期间从2020年5月1日至2021年4月30日432场中美六大组织机构举办的中文教师研训活动,比对TPACKS教师知识技能结构理论,分析培训活动的主题布局。结果显示,学科教学知识类、科技支持教学的知识类、教学法知识类研训活动最为丰富,但对科技知识、内容知识以及融合科技、教学法与学科教学的高级综合知识重视不足;另外,研究也发现大学教师独立报告人数量居多,中小学教师独立报人数量过少,但大、中小学教师跨层次合作报告为数不少,另外教师软技能研训活动也受到较大重视,特别是对国际汉语教师的跨文化技能、自我认知规划、大格局系统化思维等非传统知识技能的认识增强。

IoT-Based Cost Saving Offloading System for Cellular Networks

Nowadays, with the new techniques available in hardware and software, data requests generated by applications of mobile devices have grown explosively. The large amount of data requests and their responses lead to heavy traffic in cellular networks. To alleviate the transmission workload, offloading techniques have been proposed, where a cellular network distributes some popular data items to other wireless networks, so that users can directly download these data items from the wireless network around them instead of the cellular network.In this paper, we design a Cost Saving Offloading System（CoSOS）, where the Internet of Things（IoT） is used to undertake partial data traffic and save more bandwidth for the cellular network. Two types of algorithms are proposed to handle the popular data items distribution among users. The experimental results show that CoSOS is useful in saving bandwidth and decreasing the cost for cellular networks.