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1.
It is a common observation that whenever patients arrives at the front desk of a hospital, outpatient clinic, or other health-associated centers, they have to first queue up in a line and wait to fill in their registration form to get admitted. The long waiting time without any status updates is the most common complaint, concerning health officials. In this paper, UrNext, a location-aware mobile-based solution using Bluetooth low-energy (BLE) technology is presented to solve the problem. Recently, a technology-oriented method, the Internet of Things (IoT), has been gaining popularity in helping to solve some of the healthcare sector’s problems. The implementation of this solution could be illustrated through a simple example of when a patient arrives at a clinic for a consultation. Instead of having to wait in long lines, that patient will be greeted automatically, receive a push notification of an admittance along with an estimated waiting time for a consultation session. This will not only provide the patients with a sense of freedom but would also reduce the uncertainty levels that are generally observed, thus saving both time and money. This work aims to improve the clinics’ quality of services, organize queues and minimize waiting times, leading to patients’ comfort while reducing the burden on nurses and receptionists. The results demonstrate that the presented system is successful in its performance and helps achieves a pleasant and conducive clinic visitation process with higher productivity.  相似文献   
2.
We propose in this paper a Hybrid Software‐Defined Networking‐based Geographical Routing Protocol (HSDN‐GRA) with a clustering approach. It takes into account three different criteria to select the best relay to send data: (1) the contact duration between vehicles, (2) the available load of each vehicle, (3) and the log of encountered communication errors embedded in each cluster head. The multi‐criteria strategy allows the selection of the most reliable vehicles by avoiding communication problems and ensuring connection availability. Once the hybrid control plane has found out the next eligible neighbor, the data plane will be in charge of dividing and sending data. To validate our approach, HSDN‐GRA has been modeled and implemented in JADE, a multi‐agent platform, to be compared to other multi‐agent based protocols. Simulation results show that HSDN‐GRA achieves good performance with respect to the average routing overhead, the packet drop rate, and the throughput.  相似文献   
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Energy harvesting (EH) has been considered as a promising technology to solve the constrained energy problem in the devices of IoT with its advantages of flexible deployment and sustainable energy supply.For multiple access channel with energy harvesting,a hybrid energy storage structure model composed by super capacitor and battery was proposed for the devices of IoT.According to the peculiarities of medium access channel and energy harvesting system,an optimized energy allocation strategy with exponential-type decline (ETD) was presented,the upper and lower bounds of the average throughput were deduced,in particular,the gap of two bounds was derived to be a constant.The channel capacity was further obtained by utilizing the relationship between the average throughput and the channel capacity.In the simulations,the effect of harvested energy,storage capacity and the number of nodes on the channel capacity were analyzed respectively.Experiment results show that compared with the conventional wireless node with single battery storage,the proposed hybrid energy storage structure can improve the harvested energy value and increase the multiple access channel capacity by using adaptive modulation scheme when transmitting the signals.  相似文献   
5.
“Smart firefighting” construction as a part of the “smart city” has been a concern of the public security and fire agencies at all levels. In this study, the status, problems, and reflections of “smart firefighting” construction in China are discussed. A recent survey indicates that China has launched its smart firefighting construction and initially created a new perspective on its regional smart firefighting work based on three main aspects: intelligent disaster perception by Internet of Things (IoT) construction, intelligent disaster prevention by big data construction, and intelligent disaster disposal by emergency rescue platform construction. However, the current smart firefighting construction in China still has some prominent problems such as the data interconnectivity and normalized management of various platforms, the extensibility of smart firefighting platforms, and the intelligent level of smart firefighting researches, which need to be solved urgently. Therefore, we argue that smart firefighting construction in China should establish data interconnectivity, industrial normalized management, 2D/3D geographic information interaction and extension, high-integration fire protection theory, and many other aspects in the near future and truly realize firefighting visualization and efficient data applications for 4D time space. This study could provide valuable reference for smart firefighting and smart city construction.  相似文献   
6.
程小辉  牛童  汪彦君 《计算机应用》2020,40(6):1680-1684
随着物联网(IoT)的快速发展,越来越多的IoT节点设备被部署,但伴随而来的安全问题也不可忽视。IoT的网络层节点设备主要通过无线传感网进行通信,其相较于互联网更开放也更容易受到拒绝服务等网络攻击。针对无线传感网面临的网络层安全问题,提出了一种基于序列模型的网络入侵检测系统,对网络层入侵进行检测和报警,具有较高的识别率以及较低的误报率。另外,针对无线传感网节点设备面临的节点主机设备的安全问题,在考虑节点开销的基础上,提出了一种基于简单序列模型的主机入侵检测系统。实验结果表明,针对无线传感网的网络层以及主机层的两个入侵检测系统的准确率都达到了99%以上,误报率在1%左右,达到了工业需求,这两个系统可以全面有效地保护无线传感网安全。  相似文献   
7.
Delegation mechanism in Internet of Things (IoT) allows users to share some of their permissions with others. Cloud-based delegation solutions require that only the user who has registered in the cloud can be delegated permissions. It is not convenient when a permission is delegated to a large number of temporarily users. Therefore, some works like CapBAC delegate permissions locally in an offline way. However, this is difficult to revoke and modify the offline delegated permissions. In this work, we propose a traceable capability-based access control approach (TCAC) that can revoke and modify permissions by tracking the trajectories of permissions delegation. We define a time capability tree (TCT) that can automatically extract permissions trajectories, and we also design a new capability token to improve the permission verification, revocation and modification efficiency. The experiment results show that TCAC has less token verification and revocation/modification time than those of CapBAC and xDBAuth. TCAC can discover 73.3% unvisited users in the case of delegating and accessing randomly. This provides more information about the permissions delegation relationships, and opens up new possibilities to guarantee the global security in IoT delegation system. To the best of our knowledge, TCAC is the first work to capture the unvisited permissions.  相似文献   
8.
ABSTRACT

Smart cities are designed to use data to optimize resources, maintain sustainability, and improve people’s quality of life. While many urban technologies are employed to make cities “smart,” one constellation of technologies has been less examined in the academic literature—digital maps and the spatial data infrastructure. This paper is an attempt to systematically review the functions and evolution of digital maps and the spatial data infrastructure, with examples from Asia and beyond, in supporting and making smart cities possible. Based on the conceptual framework and empirical case studies, four major research directions of smart mapping are identified to better support smart city initiatives.  相似文献   
9.
In this paper, a low-power low-noise complementary metal-oxide semiconductor (CMOS) receiver RF front-end (RFFE) that employs a current-reuse Q-boosted resistive feedback low-noise amplifier (RFLNA) is proposed for 401 to 406 MHz medical device radio-communication service band IoT applications. By employing a series RLC input matching network, the proposed RFLNA has the advantages of both the conventional RFLNA and the inductively degenerated common-source LNA without using large on-chip spiral inductors at the sources of the main transistors. The proposed active mixer utilizes a current-reuse transconductor, in which a p-channel metal-oxide semiconductor (PMOS) transistor performs a current-bleeding function to reduce direct current (DC) and flicker noise in the switching stage of the active mixer. The proposed receiver RFFE is implemented in a 65-nm CMOS process and achieves a voltage gain of 30.9 dB, noise figure of 4.1 dB, S11 of less than −10 dB, and IIP3 of −22.9 dBm. It operates at a supply voltage of 1 V with bias currents of 360 μA. The active die area is 0.4 mm × 0.35 mm.  相似文献   
10.
随着物联网终端爆炸式的增加,物联网致密化成为发展的必然。在海量终端数量和资源严重受限的情况下,如何确定物联网终端设备的接入基站以及如何有效地为接入的用户进行资源分配,成为超密集物联网系统所需解决的重要问题。文章在吞吐量和系统能耗之间进行折中,以系统能效为优化目标,设计了一种超密集物联网中的多蜂窝网络选择算法。该算法为用户和基站设置效用函数,基于匹配理论完成用户的选择过程。最后对该算法和对比算法进行仿真,结果表明,多蜂窝网络选择算法在能耗和能效性能上均优于对比算法。  相似文献   
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