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1.
《Journal of The Franklin Institute》2022,359(17):10098-10119
This study investigates the outage performance for a wireless-powered relaying satellite-terrestrial system, which consists of a satellite source, a relay, a power beacon, and two users. In particular, the satellite source transmits its information to the relay, which uses up all the harvested energy from the power beacon with a nonlinear energy harvesting mode to forward a superimposed signal of the source and its own information under a non-orthogonal multiple access protocol. Assuming the satellite link experiences Shadowed-Rician fading and the terrestrial links undergo Nakagami-m fading distribution, the analytical expressions of outage probability for both users are presented in the presence of imperfect successive interference cancellation. In addition, the optimal power allocation factor, which can result in the best outage performance, is also obtained. Finally, Monte-Carlo simulations are used to verify the accuracy of the analytical expressions. 相似文献
2.
Zvezdan M. Marjanović Goran T. Djordjević Gradimir V. Milovanović 《Journal of The Franklin Institute》2018,355(2):965-980
In this paper, we analyze detection of multilevel phase-shift keying (MPSK) signals transmitted over a Gamma shadowed Nakagami-m fading channel. We derive novel analytical expression, in terms of Meijer’s G function, for Fourier coefficients of the probability density function of the received signal composite phase. Under the assumption of the imperfect reference signal extraction in the receiver, which is performed from the pilot signal, the analytical expression is derived for the symbol error probability (SEP) in the form of convergent series. The existence of the error floor is identified, and expression for its computation is provided. Mathematical proofs for convergence of Fourier series are provided for both SEP and SEP floor, and novel expressions of upper bounds for truncation errors are derived in terms of elementary mathematical functions. The convergence rate of the derived expressions is examined. Numerical results are confirmed independently by Monte-Carlo simulations. 相似文献
3.
《Journal of The Franklin Institute》2023,360(8):5354-5374
In this paper, we provide a methodology to evaluate the capacity of a Massive multiple-input multiple-output (MIMO) supported Internet of Things (IoT) system in which a large number of low cost low power IoT devices transmit and receive sporadic data. Numerous IoT devices are supported by a single cell Massive MIMO base station (BS) with maximum-ratio (MR) processing. Orthogonal reference signals (RSs) or pilots are assigned randomly to all the IoT devices for channel estimation purpose. The number of simultaneously active IoT devices follows Poisson distribution. Due to the tremendous number of IoT devices, orthogonal RSs are heavily reused, which severely degrades the receiver signal quality. One of the most important performance criteria for this kind of system is the blocking probability which shows the percentage of the outage IoT devices, and how we maintain the low blocking probability while supporting all the IoT devices simultaneously is particularly important. Due to RS reuse, we can divide IoT devices into two groups based on their interference levels. We provide detailed theoretical analyses, and show that the blocking primarily happens to the group with higher interference level. Increasing the number of service antennas and/or reducing the number of IoT devices can help to improve the performance of the blocking probability, however there is a regime in which the parameter adjustment helps little to improve the performance. Based on these factors, we provide a useful algorithm to improve the performance of blocking probability. A number of simulation results are also provided to validate the theoretical analysis. 相似文献
4.
Most firms use secrecy to protect their knowledge from potential imitators. However, the theoretical foundations for secrecy have not been well explored. We extend knowledge protection literature and propose theoretical mechanisms explaining how information visibility influences the importance of secrecy as a knowledge protection instrument. Building on mechanisms from information economics and signaling theory, we postulate that secrecy is more important for protecting knowledge for firms that have legal requirements to reveal information to shareholders. Furthermore, we argue that this effect is contingent on the location in a technological cluster, on a firm’s investment in fixed assets and on a firm’s past innovation performance. We test our hypotheses using a representative sample of 683 firms in Germany between 2005 and 2013. Our results support the moderation effect of a technological cluster and a firm’s investment in fixed assets. Our findings inform both academics and managers on how firms balance information disclosure requirements with the use of secrecy as a knowledge protection instrument. 相似文献
5.
《Information processing & management》2023,60(2):103212
The massive number of Internet of Things (IoT) devices connected to the Internet is continuously increasing. The operations of these devices rely on consuming huge amounts of energy. Power limitation is a major issue hindering the operation of IoT applications and services. To improve operational visibility, Low-power devices which constitute IoT networks, drive the need for sustainable sources of energy to carry out their tasks for a prolonged period of time. Moreover, the means to ensure energy sustainability and QoS must consider the stochastic nature of the energy supplies and dynamic IoT environments. Artificial Intelligence (AI) enhanced protocols and algorithms are capable of predicting and forecasting demand as well as providing leverage at different stages of energy use to supply. AI will improve the efficiency of energy infrastructure and decrease waste in distributed energy systems, ensuring their long-term viability. In this paper, we conduct a survey to explore enhanced AI-based solutions to achieve energy sustainability in IoT applications. AI is relevant through the integration of various Machine Learning (ML) and Swarm Intelligence (SI) techniques in the design of existing protocols. ML mechanisms used in the literature include variously supervised and unsupervised learning methods as well as reinforcement learning (RL) solutions. The survey constitutes a complete guideline for readers who wish to get acquainted with recent development and research advances in AI-based energy sustainability in IoT Networks. The survey also explores the different open issues and challenges. 相似文献
6.
国外农业物联网技术发展及对我国的启示 总被引：5，自引：0，他引：5
随着现代信息技术的发展,物联网已广泛应用于农业生产的各个领域。国际上,一些国家在农业物联网感知技术、数据传输技术、智能处理技术等方面取得了重要的进展,出现了物联网在农业领域的典型应用。这些技术进展和相关应用对我国农业物联网的快速发展具有重要的借鉴意义。文章通过对国外农业物联网技术最新进展的调研和分析,描述了农业物联网在感知技术、数据传输技术、智能处理技术等方面的国际先进经验,例举了国外农业物联网在农业资源监测和利用、农业生态环境监测、农业生产精细管理、农产品安全溯源、农业物联网云服务等领域的典型应用,并针对我国农业物联网技术的发展,在发展微型化传感器、寻求系统节能策略、努力降低传感器成本、传感器网络安全性和抗干扰问题、节点自动配置问题等方面提出了建设性意见。 相似文献
7.
J.S. Stecki 《Journal of The Franklin Institute》1981,311(2):93-110
Kinematically constrained motion is generally accepted as a fundamental requirement for a mechanism to function as a power transmitting device. There exists, however, a class of mechanism which although kinematically unconstrained, can, by incorporation of energy storage elements, function as a power transmitter. An example of such a mechanism is the automatic, variable ratio power transmission invented in the early twenties by G. Constantinesco, which generated a lot of interest among the engineering fraternity at the time. A typical device consists of a crank-driven nine-bar mechanism which possesses two degrees of mobility. The single velocity (or torque) source supplies the input power, which is transmitted to the output shaft by means of unidirectional drives. The characteristics of the energy storage element in conjunction with a single velocity (or torque) input and the external load fully determine the dynamic behavior of the device. During operation, the input energy is distributed between the load and the energy storage depending on the requirements of the load. For a given input power and external load, the device will adjust the velocity of the output shaft to absorb that power; i.e., it will operate as an automatic, variable ratio power transmission.This paper concentrates on the formulation of a general bond graph model for the mechanism. The model possesses mixed causality and non-linear structure. Some results of digital simulation of the bond graph model of a particular mechanism are provided. 相似文献
8.
中外信息保密的立法精神比较及其思考 总被引：2，自引：0，他引：2
本文从秘密信息的法律保护及其特点出发,对中外主要国家信息保密的立法精神,从立法观念、立法指导思想两个方面进行了比较分析,并对建立健全我国信息保密法律制度提出了建设性的意见。 相似文献
9.
10.
S.G. Tzafestas 《Journal of The Franklin Institute》1976,302(1):19-36
The buffer design problem is studied for the cases where there exist single- and multiple-input lines with Poisson or Poisson bursts arrivals, periodic block or batch type removals, and binomial feedback.Using traffic intensity σ, block size c, and the feedback probability Pa as parameters, the analytical expressions concerning the average fractional information loss, the channel utilization and the average buffering delay in relation to the buffer length are derived. These relationships are computed for a set of parameter values and are plotted to be used as a basis for the buffer design. The present study should be valuable in designing engineering systems such as time sharing computer systems, information compression systems, computer networks, road traffic simulators, telephone exchanges etc. An illustrative example of a single-input buffer system of the type considered is fully discussed. 相似文献
11.
《Journal of The Franklin Institute》2023,360(12):8973-8996
In this paper, the measurement outlier-resistant target tracking problem is investigated in wireless sensor networks (WSNs) with energy harvesting constraints. Each WSN node can acquire energy stochastically from surroundings. No matter whether the WSN node acquires energy or not, the WSN node’s measurement can be transmitted if the energy amount of the WSN node is greater than zero. In such a case, the sensor energy-induced missing measurement (SE-IMM) phenomenon may occur. The objective of this paper is to develop a solution for the considered target tracking problem by devising the filter including a saturation constraint such that, in the simultaneous presence of outliers and the SE-IMM phenomenon, the tracking performance can meet the given performance index. Firstly, the relation between the energy level of the WSN node and its probability distribution is computed recursively. Then, an upper bound of the tracking error covariance is derived which is minimized by appropriately choosing the filter parameter. Finally, the feasibility of the proposed target tracking scheme is validated by conducting a set of comparative experiments and the relationship between the energy of the WSN node and the tracking performance is also disclosed. 相似文献
12.
《Information processing & management》2020,57(2):102065
In this article, we present a conceptual framework of information needs for task-based information studies. The framework accounts for both vertical and horizontal relationships between information needs as fluid activities in work-task performance. As part of task performance, pieces of information are gathered from various, heterogeneous sources, not primarily to fulfil any expressed formulation of information needs, but in order to make progress in the task. The vertical relationships pinpoint connections between general and specific, from the workplace context to the interaction with an information source, and the horizontal relationships between parallel information needs. These relationships enrich the conceptual understanding of information needs in information studies, which previously has focussed on sequential relationships. The sequential, vertical and horizontal relationships form an analytical network that allows a departure from the black-box depiction of information needs. 相似文献
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14.
首先运用流程图法分析造成物联网环境下医药冷链物流各环节风险的众多因素源,并运用熵权法对风险指标客观赋权建立风险因素评估指标体系,然后利用Ge NIe软件建立动态贝叶斯网络模型对风险环节的关键风险因素进行概率评估。结果显示在风险评估中运输环节风险的发生概率最高,同时企业关于设备的验证选型是影响物联网医药冷链的关键风险因素,这为企业和政府控制药品质量安全管理提供了依据。 相似文献
15.
当前,理论界与实践界都认为企业需要构建恰当的物联网商业模式,从而有效地释放和获取物联网技术的商业价值。为此,运用模块化理论深入解析物联网商业模式的复杂结构、可能形态与构建路径。研究发现:用户企业物联网商业模式是由能够独立设计而又功能集成的技术模块和业务模块构成;按照用户企业处理看得见的设计规则可将物联网商业模式划分为封闭型、开放型与自适应型3种类型;用户企业通过模块整合构建物联网商业模式,包括技术模块整合、技术模块与业务模块整合、跨企业的模块整合3个层次。 相似文献
16.
Si-Yuan Yu Cheng He Xiao-Chen Sun Hong-Fei Wang Ji-Qian Wang Zi-Dong Zhang Bi-Ye Xie Yuan Tian Ming-Hui Lu Yan-Feng Chen 《国家科学评论(英文版)》2021,8(2)
Waveguides and resonators are core components in the large-scale integration of electronics, photonics and phononics, both in existing and future scenarios. In certain situations, there is critical coupling of the two components; i.e. no energy passes through the waveguide after the incoming wave couples into the resonator. The transmission spectral characteristics resulting from this phenomenon are highly advantageous for signal filtering, switching, multiplexing and sensing. In the present study, adopting an elastic-wave platform, we introduce topological insulator (TI), a remarkable achievement in condensed matter physics over the past decade, into a classical waveguide-ring-resonator configuration. Along with basic similarities with classical systems, a TI system has important differences and advantages, mostly owing to the spin-momentum locked transmission states at the TI boundaries. As an example, a two-port TI waveguide resonator can fundamentally eliminate upstream reflections while completely retaining useful transmission spectral characteristics, and maximize the energy in the resonator, with possible applications being novel signal processing, gyro/sensing, lasering, energy harvesting and intense wave–matter interactions, using phonons, photons or even electrons. The present work further enhances confidence in using topological protection for practical device performance and functionalities, especially considering the crucial advantage of introducing (pseudo)spins to existing conventional configurations. More in-depth research on advancing phononics/photonics, especially on-chip, is foreseen. 相似文献
17.
Debora Halbert 《The Information Society》1997,13(4):361-374
This article argues that the hacker is constructed as an information deviant and that this image is helpful in providing rules for appropriate behavior in an information society. The hacker accounts in this article are designed to give the reader an understanding of the types of things being said about hackers. What is more important, however, is how these narratives are used to support a specific notion of property ownership and government secrecy. In making this argument, this article traces the development of the narrative about the hacker from harmless computer nerd to terrorist. 相似文献
18.
With the development of information technology and economic growth, the Internet of Things (IoT) industry has also entered the fast lane of development. The IoT industry system has also gradually improved, forming a complete industrial foundation, including chips, electronic components, equipment, software, integrated systems, IoT services, and telecom operators. In the event of selective forwarding attacks, virus damage, malicious virus intrusion, etc., the losses caused by such security problems are more serious than those of traditional networks, which are not only network information materials, but also physical objects. The limitations of sensor node resources in the Internet of Things, the complexity of networking, and the open wireless broadcast communication characteristics make it vulnerable to attacks. Intrusion Detection System (IDS) helps identify anomalies in the network and takes the necessary countermeasures to ensure the safe and reliable operation of IoT applications. This paper proposes an IoT feature extraction and intrusion detection algorithm for intelligent city based on deep migration learning model, which combines deep learning model with intrusion detection technology. According to the existing literature and algorithms, this paper introduces the modeling scheme of migration learning model and data feature extraction. In the experimental part, KDD CUP 99 was selected as the experimental data set, and 10% of the data was used as training data. At the same time, the proposed algorithm is compared with the existing algorithms. The experimental results show that the proposed algorithm has shorter detection time and higher detection efficiency. 相似文献
19.
《Research Policy》2022,51(10):104600
Innovative industries need efficient markets for technology (MFTs). One determinant of MFT efficiency neglected until now is licensing level—that is, the level in the value chain where patents are licensed. Patents may be licensed upstream, to firms that put the patented knowledge into practice. I refer to this as integrated licensing. Alternatively, patents may be licensed further downstream in the value chain, in particular to makers of final devices. I call this bifurcated licensing since it separates intellectual property rights from the technical knowledge they cover. I study the licensing level of essential patents on communication standards such as LTE and Wi-Fi in relation to the Internet of Things (IoT). The choice of licensing level in this context is currently a hotly debated topic. To show how bifurcated licensing affects MFT efficiency, I present empirical evidence from a qualitative study comprising interviews with 30 individuals from 22 diverse firms, focusing on startups. IoT device makers clearly find the uncertainty regarding infringement, patent validity, and the licensing process hinders efficient licensing, which is compounded by the large number of IoT device makers and, for SMEs and startups, by resource constraints. As a theory contribution, I show that a patent's licensing level need not correspond with the implementation level of the patented knowledge—in other words, licensing may be bifurcated rather than integrated. I develop a model of how licensing level affects MFT efficiency. Implications for practice are that device-level licensing of standard-essential patents (SEPs), if broadly implemented, would have a negative effect on innovation and entrepreneurship in the IoT. Policymakers should ensure that SEP licensing is simplified. 相似文献
20.
《Information processing & management》2022,59(2):102869
User-created automation applets to connect IoT devices and applications have become popular and widely available. Exploring those applets enables us to grasp the patterns of how users are utilizing and maximizing the power of connection by themselves, which can deliver practical implications for IoT service design. This study builds an IoT application network with the data of the IFTTT(if this then that) platform which is the most popular platform for self-automation of IoT services. The trigger-action relationships of the IFTTT applets currently activated are collected and used to construct an IoT application network whose nodes are IoT service channels, and links represent their connections. The constructed IoT network is then embedded by the node2vec technique, an algorithmic framework for representational learning of nodes in networks. Clustering the embedded nodes produces the four clusters of IoT usage patterns: Smart Home, Activity Tracking, Information Digest, and Lifelogging & Sharing. We also predict the IoT application network using node2vec-based link prediction with several machine learning classifiers to identify promising connections between IoT applications. Feasible service scenarios are then generated from predicted links between IoT applications. The findings and the proposed approach can offer IoT service providers practical implications for enhancing user experiences and developing new services. 相似文献