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This article provides a method based on self-organizing maps (SOM) neural network clustering and support vector machine (SVM) ensembles to predict the survival risk levels of esophageal cancer. Nine blood indexes related to patient survival are found by using SOM clustering method. Two critical thresholds for survival are found by plotting the receiver operating characteristic (ROC) curve twice, and the lifetime is divided into three risk levels. Using the SVM method, patients' risk levels are predicted and assessed. Four kernel functions of SVM are compared, and the prediction effect of RBF kernel function is better than other kernel functions. The parameters of SVM are optimized by using genetic algorithm (GA), particle swarm algorithm (PSO) and artificial bee colony (ABC) algorithm. Experimental results show that the prediction accuracies are improved by using optimization algorithms. After comparison, ABC-SVM has better prediction results than GA-SVM and PSO-SVM with a high prediction rate and fast running time.

In this paper, a novel design named security-oriented polar coding (SOPC) is proposed to enhance the physical layer security (PLS), where the active pattern of frozen bits in a transmission is determined by random channel gain of the legitimate link. Since the channel gain value is not exchanged between the legitimate transmitter and the desired receiver, eavesdroppers cannot ascertain the frozen bit pattern engaged in the legitimate polar coding. When the signal-to-noise ratio (SNR) is low, eavesdroppers are unable to appropriately decode the confidential information delivered over the legitimate link. As the SNR increases, eavesdroppers may have chance to sort out the correct frozen bit pattern through a brute-force search. However, this chance is significantly reduced by our SOPC. We design the SOPC for both single-input-single-output single-antenna eavesdropper (SISOSE) and multiple-input-multiple-output multi-antenna eavesdropper (MIMOME) channels. Its PLS functioning is assessed in terms of the error rate difference between the legitimate receiver and the eavesdropper. Illustrative simulation results substantiate that the SOPC design guarantees degraded decoding performance at eavesdroppers, for both SISOSE and MIMOME channels, even in the presence of a powerful eavesdropper possessing infinite computational resources.

Insecticidal lamps Internet of things (ILs-IoT) has attracted considerable attention for its applications in pest control to achieve green agriculture. However, ILs-IoTs cannot provide a perfect solution to the migratory pest outbreak if the ILs are fixed on the ground. In this paper, we embed ILs in unmanned aerial vehicles (UAVs) as the mobile nodes, which can be rapidly landed on the ground to kill agricultural pests, and the Internet of UAVs (IoUAV) is introduced to extend the application of ILs-IoTs. To take full advantage of the IL-IoUAVs, we formulate the problem of target-barrier coverage and investigate how to minimise the number of IL-UAVs in constructing the target-barrier coverage. The target-barrier coverage is introduced utilizing the realistic probabilistic sensing model of IL-UAVs, based on which we study how to guarantee the target-barrier coverage while minimizing the number of IL-UAVs needed. The problem is solved by an optimal algorithm to merge multiple target-barriers. Evaluation results show the efficiency of our designed algorithms for constructing target-barrier coverage.

As the digital version of a continuous-time delay, the concept of fractional delay (FD) is exploited to approximate a desired delay that is not a multiple of the sampling interval. However, in FD filters, there is always a severe distortion at the beginning of delayed signals, referred to as head distortion . This letter identifies the cause of head distortion and proposes a solution to this problem for reducing the overall distortion in FD filters. For the purpose of performance evaluation, relative root-mean-square (RMS) error is formulated as a metric to quantify the overall difference between the frequency-domain response of an FD filter and the ideal one. Moreover, illustrative numerical results on the proposed scheme applied in FD filters with classical sinc, Farrow and Lagrange interpolation substantiate the validity and feasibility of our solution.

In this paper, the concept of opportunistic bits (OBs) is developed in short-packet communications and investigated from a finite blocklength perspective. In the OB-based transmission, the data unit of a packet is divided into two parts: OBs and conventional bits (CBs). The OBs are not physically transmitted but used to indicate the index of the time slot (TS) when the packet containing CBs is transmitted. The loading of a bulk of OB-based packets into multiple TSs can be modelled as a Repeated Balls-into-Bins process with a multi-queue storage. If the bulk is not large enough, certain combination(s) of OBs will not appear, which leaves certain TS(s) empty and hence reduces the TS load efficiency. To evaluate the OB-based transmission performance, we formulate its maximal payload rate and TS load efficiency. With the aid of these two formulations, the energy gain, the goodput, and the latency of OB-based short-packet communications are derived and obtained in analytical forms. For achieving further insights, illustrative numerical results on the resource utilisation efficiency and the performance not only substantiate the advantages of the OB-based transmission over the conventional but also provide useful tools and specifications for its design in massive short-packet communications.

In this paper, a decode-and-forward (DF) short-packet relaying model is developed to achieve timely status updates for intelligent monitoring within the Internet of Things (IoT), where the status updates generated at an IoT device are delivered to a remote server with the aid of a relay in both half-duplex (HD) and full-duplex (FD) modes. To characterise the data freshness of status updates, we exploit the age of information (AoI) as a metric, which is defined as the time elapsed since the generation of the latest successfully decoded status update. The average AoI is formulated and minimised for both HD-DF and FD-DF relaying IoT networks in finite blocklength regime. For the HD-DF relaying, we introduce a perfect approximation of the average AoI to solve the problem of average AoI minimisation with the optimal blocklengths in two phases. For the FD-DF relaying, we propose an iterative algorithm to solve the problem of average AoI minimisation by optimising the relay’s transmit power and the blocklength. Illustrative numerical results not only substantiate the validity of our proposed algorithms, but also provide useful references for the IoT monitoring network design, specifically for the transmit power thresholds at the IoT device and the relay.

In this paper, a novel permutation-based transmission strategy is proposed to improve the goodput in wireless networks for achieving ultra-reliable and low-latency communications. The proposed scheme divides the application-layer data into two portions: the first one is conveyed by the permutation with repetition of various lengths in a group of packets rather than encapsulated into the packets, whilst the second portion is encapsulated into these packets to be physically delivered through network interface in the conventional way. The lengths of the packets used to deliver the second portion are determined by the first one. Thanks to the goodput gain attained by the permutation-conveyed application-layer data, the network congestion is alleviated, which leads to lower latency and/or less dropped packets. The validity of this transmission strategy is substantiated by the analysis in the metrics of goodput, latency, physical-layer throughput and secrecy rate within a design paradigm of short-packet communications.

As an important physical control technology, Solar Insecticidal Lamp (SIL) can effectively prevent and control the occurrence of pests. The combination of SILs andWireless Sensor Networks (WSNs) initiates a novel agricultural Internet of Things (IoT), i.e., SIL-IoTs, to simultaneously kill pests and transmit pest information. In this paper, we study the weighted SIL Deployment Problem (wSILDP) in SIL-IoTs, where weighted locations on ridges are prespecified and some of them are selected to deploy SILs. Different from the existing studies whose optimization objective is to minimise the deployment cost, we consider the deployment cost and the total weight of selected locations jointly. We formulate the wSILDP as the Weighted Set Cover (WSC) problem and propose a Layered Deployment Method based on Greedy Algorithm (LDMGA) to solve the defined optimization problem. The LDMGA is composed of two phases. Firstly, SILs are deployed layer by layer from the boundary to the centre until the entire farmland is completely covered. Secondly, on the basis of three design operations, i.e., substitution, deletion and fusion, the suboptimal locations obtained in the first phase are fine-tuned to achieve the minimum deployment cost together with the maximum total weight for meeting the coverage and connectivity requirements. Simulation results clearly demonstrate that the proposed method outperforms three peer algorithms in terms of deployment cost and total weight.

To achieve physical layer security (PLS) with a flexible implementation, a novel design named security-oriented trellis coded spatial-modulation (SO-TCSM) is proposed in this paper, where the transmitter does not know the channel state information (CSI) of wiretapping channels and relies on the legitimate CSI to vary the mapping patterns for the antenna information and the radiated information, aiming at the optimisation of free Euclidean distances between the resultant SO-TCSM symbols. Eavesdroppers cannot decode the confidential information delivered in the legitimate link, as they do not know the legitimate CSI and, hence, have no basis to acquire the transmitter's mapping pattern of the moment. Moreover, the SO-TCSM symbols are then compensated to maximise their Euclidean distances, which further improves the legitimate receiver's decoding performance while enhancing the PLS. However, the compensation results in high transmit power when the legitimate channels are in deep fades. To boost the energy efficiency, a constraint is set to limit the transmit power. Under this constraint, the SO-TCSM performance is investigated in terms of bit error rate and transmit power consumption. The outcome of these investigations substantiates that, compared to conventional TCSM designs, our SO-TCSM achieves better performance in the legitimate link with lower decoding complexity.

The paper proposed a method that organizes a parallel transmission of two signals to be separated from each other at receiver through Hamming-to Euclidean space, where the conventional problem of achievable bit rate (ABR) is converted to that of the ABR’s summation with respect to the two separated signals. Actually, the mutual information is separated accordingly into two. Since the mutual information is non-linear function of signal power in general, the separation brings a chance for achieving higher ABR. The proposed work proceeds along the above thinking and achieves higher bit-error-rate (BER) performance in comparison with BPSK as shown in the simulations. Moreover, one can find theoretically beyond of channel capacity of BPSK input.

Frequency measurement based on dual THz frequency combs of photocarrier (dual PC-THz combs) is a promising method for the real-time measurement of the absolute frequency in CW-THz radiation without the need for cryogenic cooling. However, use of dual femtosecond lasers hinders the practicability of this method. In this paper, we generated dual PC-THz combs using a free-running, dual-wavelength mode-locked fiber laser, and applied the resulting dual PC-THz comb for the real-time monitoring of the absolute frequency in CW-THz radiation.

In this paper, a novel artificial-noise strategy is proposed for single-antenna point-to-point systems over multi-path fading channels. Unlike existing artificial-noise schemes that are used in multi-antenna systems for the only purpose of confusing eavesdroppers, the main objectives of the artificial noise generated in the proposed strategy are not only to guarantee secure communications, but also to compensate inter-symbol interference induced by multi-path propagation while achieving full multi-path diversity in the desired link between source and legitimate destination. Based on maximal-ratio combining at the destination, the artificial noise herein is specified by the channel state information (CSI) of the desired link. Specifically for the time-division duplex mode, thanks to channel reciprocity, the CSI is available at the source to generate the artificial noise. However, third-party eavesdroppers that are blind to the CSI are not able to decode the source information injected with the artificial noise. Illustrative discussions on the performance not only substantiate the validity of the proposed strategy both in overcoming multi-path effects and for physical layer security, but also provide a useful tool for the frame design with the proposed strategy.

In this paper, a hierarchical cell structure is considered, where public safety broadcasting is fulfilled in a femtocell located within a macrocell. In the femtocell, also known as local cell, an access point broadcasts to each local node (LN) over an orthogonal frequency sub-band independently. Since the local cell shares the spectrum licensed to the macrocell, a given LN is interfered by transmissions of the macrocell user (MU) in the same sub-band. To improve the broadcast performance in the local cell, a novel scheme is proposed to mitigate the interference from the MU to the LN while achieving diversity gain. For the sake of performance evaluation, ergodic capacity of the proposed scheme is quantified and a corresponding closed-form expression is obtained. By comparing with the traditional scheme that suffers from the MU's interference, numerical results substantiate the advantage of the proposed scheme and provide a useful tool for the broadcast design in hierarchical cell systems.

Current research on scheduling of workflow applications in Cloud environment is main focused on the trade-off between the execution cost and time of a task. However, unlike traditional scheduling, there are other important requirements to be taken into account. One such a requirement is trust scheduling, namely selecting trustful compute resources and data hosts so that the execution of applications. In this paper, we formulate the scheduling problem for workflow applications with trust constraints and present a novel scheduling algorithms based on trust. Experimental results illustrate that the proposed heuristic scheduling algorithm is better than the traditional algorithm for scheduling application workflows, and can find the most trusted execution flow efficiently.

In this work, we consider a cooperative network where multiple relay nodes having different modulation capabilities assist the end-to-end communication between a source and its destination. Firstly, we evaluate the effective capacity (EC) performance of the network under study. According to the analysis, an EC-based relay selection criterion is proposed. Based on the proposed selection rule and half-duplex decode-and-forward protocol, the activated relays cooperatively help with the packet transmission from the source. At the destination, packet combining is taken into account to improve the quality of service. Compared to the popular scheme, opportunistic relay selection, numerical results are provided to prove the validity and advantages of our proposed scheme in certain scenarios. Moreover, the analysis presented herein offers a convenient tool to the relaying transmission design, specifically on which relay selection scheme should be used as well as how to choose the receiving strategy between with and without packet combining at the destination.

In this paper, we consider a broadcast channel in spectrum-sharing networks, where the base station schedules licensed primary users (PUs) and cognitive secondary users (SUs) simultaneously. Based on such a framework, we present a transmission strategy in the light of dirty paper coding. In order to promise the PUs' quality of service (QoS) in the broadcasting, the base station chooses codewords for the users by taking into account that the codewords pertaining to SUs can be pre-subtracted from those pertaining to PUs as if there were no interference from the secondary's data to the primary's data. For the purpose of performance evaluation, by taking capacity behavior and bit error rate (BER) as metrics, we study the achievable data rate regions for both types of users with the introduced design, and analyze the BER performance in corresponding systems implemented with hierarchical modulation. Numerical results substantiate that with flexible management of the spectrum resources, our proposed scheme provides more communication opportunities for SUs while maintaining PUs' QoS at an acceptable level.

In this paper taking structure parameters as variables, and considering the mechanical restriction and temperature rise in it, we study the maximal force and minimal coil inductance. Based on fundamental of genetic algorithm (GA), we use its eximious character and associate with trait of Radial Bearing, Using dynamic programming, we construct mathematical model of Radial Bearing, thereby solve its it's Multi-Objective Optimization.

In this paper, we focus on a cognitive radio network where adaptive modulation is adopted in primary links. The gap between the primary user (PU)'s received signal-to-noise ratio (SNR) and the lower SNR boundary of the modulation mode that is being used, provides an interference-tolerable zone. Based on this gap, a secondary user (SU) has an increased opportunity to access the licensed spectrum and to determine the transmit power it should use to keep the PU's quality-of-service (QoS) unaffected. However, since the SU cannot obtain perfect information on the PU's received SNR, it has to choose an SNR point between the lower and upper boundaries of the PU's current modulation mode as if this point were the real SNR received by the PU. Considering this issue, in order to quantify the effect of the SU's transmissions on the PU's QoS, we define the PU's service outage probability and obtain its closed-form expressions by taking into account whether the peak transmit power constraint is imposed on the secondary's transmission or not. Subsequently, we derive the SU's achievable data rate in closed form for counterpart scenarios. Numerical results provided here quantify the relation between the PU's service outage probability and the SU's achievable data rate, which further demonstrate that the higher the peak transmit power a secondary transmitter can support, the better performance the cognitive radio network can achieve.

Libraries are facing many challenges by ICT and digital revolution. The role of library professionals is also changing: they act as cybrarian instead of librarians. Librarians are playing integrated roles beyond their traditional jobs. In this paper, we discuss the impact of IT on requirements for librarian jobs in the digital age by analyze librarian employment ads to reveal: What are educational backgrounds required or librarian positions? What are the most common job titles for librarian positions? What implication will outcome of this study provide for LIS education in China? The analysis of librarian employment advertisements will be valuable to library educators in understanding current and emerging staffing patterns and designing effective curricula in China.

Although there are a lot of researches on Information Management and Information System education in China, little research is done in examining the impact of IT on doctoral curricula by Information Management and Information System programs in China to reveal: what courses are offered? what is the most popular subject area? how Information Management and Information System schools change their curricula to meet today's challenges? In order to address above questions, this study gives a brief summary of the curricula of Information Management and Information System doctoral programs in China. Findings show that there is no national consensus of what should be the core of the Information Management and Information System discipline for PhD education in China. The largest percentage of the courses offered relate to Management Science and Engineering. Interdisciplinarity is also featured within the Information Management and Information System PhD curricula in China.

Under spectrum-sharing constraints, we consider the secondary link exploiting cross-layer combining of adaptive modulation and coding (AMC) at the physical layer with truncated automatic repeat request (T-ARQ) at the data link layer in cognitive radio networks. Both, basic AMC and aggressive AMC, are adopted to optimize the overall average spectral efficiency, subject to the interference constraints imposed by the primary user of the shared spectrum band and a target packet loss rate. We achieve the optimal boundary points in closed form to choose the AMC transmission modes by taking into account the channel state information from the secondary transmitter to both the primary receiver and the secondary receiver. Moreover, numerical results substantiate that, without any cost in the transmitter/receiver design nor the end-to-end delay, the scheme with aggressive AMC outperforms that with conventional AMC. The main reason is that, with aggressive AMC, different transmission modes utilized in the initial packet transmission and the following retransmissions match the time-varying channel conditions better than the basic pattern.

In this paper, a design for the multiple-input-multiple-output~(MIMO) multiuser transmission in the cognitive radio network is developed and its end-to-end performance is investigated under spectrum-sharing constraints. Firstly, the overall average packet error rate is analyzed by considering the channel state information feedback delay and the multiuser scheduling. Then, we provide corresponding numerical results to measure the performance evaluation for several separate scenarios, which presents a convenient tool for the cognitive radio network design with multiple secondary MIMO users.

In this paper, we consider an underlay cognitive relaying network consisting of multiple secondary users and introduce a cooperative transmission protocol using a common relay to help with the communications between all secondary source-destination pairs for higher throughput and lower realization complexity. A whole relay-assisted transmission procedure is composed of multiple access phase and broadcast phase, where the relay is equipped with multiple antennas, and the secondary sources and destinations are single-antenna nodes. Considering the spectrum-sharing constraints on the secondary sources and the relay, we analyze the capacity behaviors of the underlay cognitive relaying network under study. The corresponding numerical results provide a convenient tool for the presented network design and substantiate a distinguishing feature of introduced design in that multiple secondary users' communications do not rely on multiple relays, hence allowing for a more efficient use of the radio resources.

Information-guided channel-hopping technique employing multiple transmit antennas was previously proposed for supporting high data rate transmission over fading channels. This scheme achieves higher data rates than some mature schemes, such as the well-known cyclic transmit antenna selection and space-time block coding, by exploiting the independence character of multiple channels, which effectively results in having an additional information transmitting channel. Moreover, maximum likelihood decoding may be performed by simply decoupling the signals conveyed by the different mapping methods. In this paper, we investigate the achievable spectral efficiency of this scheme in the case of having channel estimation errors, with optimum pilot overhead for minimum mean-square error channel estimation, when transmitting over block-fading channels. Our numerical results further substantiate the robustness of the presented scheme, even with imperfect channel state information.

The task of multicast is to deliver common information to all users in a group. However, these users' different channel qualities result in their decoding capabilities being different. Therefore, the multicast design faces a dilemma to convey common information in terms of different decoding capabilities. Motivated by this, a multicast transmission scheme is proposed in this paper. In the proposed scheme, the base station transmitter prescribes the modulation and coding scheme to be used, considering the difference between the better channel-case and worse channel-case users' decoding capabilities, and the adaptive hierarchical modulation promises that each users can process the received signals according to his own decoding capabilities. Compared to the traditional multicast transmission with fixed data rate, the numerical results prove the efficiency of the proposed scheme in exploiting the users' decoding capabilities.

In this paper, we consider the relay selection problem for the cooperative transmission in wireless networks with multiple half-duplex relay nodes. In the existing scheme, by using multiple relay nodes, spatial diversity is exploited to improve the transmission reliability. However, only one relay node is active in each relay-help transmission. We propose a novel relay selection scheme to improve relay throughput by selecting more than one relay nodes in the relay-help transmission and using the selection of active relay nodes to map a portion of information to be relayed. In the proposed scheme, extra relayed information can be forwarded besides the basic relayed information transmitted traditionally, and moreover, iterative decoding can be used to achieve robust detection. Especially, we show the efficiency of the proposed scheme by analyzing its capacity performance and comparing with that of the existing scheme.

Machines are becoming the important part of the communication network, from industry to smart homes. The machine-to-machine (M2M) communication is the main mode of these machines, which automatically serves the human in the various ways. More and more M2M applications are based on the cellular networks, taking the advantages of better coverage and lower network deployment cost. However, the current cellular network is designed for the communication between human beings, which targets the voice/media transportation, low access delay and high throughput. Currently, the machine terminals connected in cellular networks are more like mobile phones, implying the complex protocol stack, power consuming and high cost, which are the main obstacles of the deployment of machines. The paper discusses the new cellular based M2M architecture which provides better support of M2M communication with much less complexity and thus lower development cost.

In this paper, a novel relay selection scheme is proposed for the wireless network with multiple half-duplex relay nodes, which improves relay throughput by selecting more than one relay nodes in each relay-help transmission and using the selection of active relay nodes to map a portion of information to be relayed. Compared with the existing relay selection scheme with only one active relay node in each relay-help transmission, the proposed scheme allows extra relayed information to be forwarded besides the basic relayed information transmitted traditionally. And, the efficiency of the proposed scheme is shown by the analysis of capacity behaviors. I. INTRODUCTION

In this paper, we consider a half-duplex relay channel where the relay node cannot transmit and receive simul- taneously. The information to be transmitted at the source node is composed of relayed information and non-relayed information. They interfere with each other in the existing scheme when the relay node forwards the relayed information and simultaneously the source node transmits the non-relayed information. In order to improve the transmission reliability, we propose two schemes where the source node chooses the non-relayed information codeword in terms of dirty paper coding (DPC). In Scheme 1, DPC technique is applied during the listening phase; and in Scheme 2, DPC technique is applied during the cooperative phase. Specially, we discuss the capacity behaviors of the proposed schemes and compare them with the baseline, namely the capacity behaviors of the existing scheme without the application of DPC technique. The corresponding numerical results prove that both proposed schemes outperform the existing scheme in the sense of capacity performance.

In the open-loop multiple input multiple output (MIMO) multicast network, space-time block coding (STBC) is a remarkable transmission scheme with an elegant mathematical solution and full diversity. However, the open-loop design has no special strategies for the worst channel-case user, whereas the multicast design need pay more attention to the worst channel- case user than the average performance with respect to all users in the multicast group. This paper is motivated by the need for certain application of limited channel state information feedback in the MIMO multicast network. The maximum selection in the MIMO unicast network is extended to the MIMO multicast network and some relevant design principles are proposed. Specifically, we investigate some basic information theory results that promise some advantages of using the proposed schemes. Compared to the baseline, i.e., the capacity behavior of the open-loop STBC scheme, we present some scenarios for the application of the proposed schemes.

In this paper, we deal with the capacity behavior of a new scheme, information-guided channel-hopping, which is proposed for high information rate communication over Rayleigh fading channel using multiple transmit antennas. This scheme is devised based on the fact that the independence character of the fading channels from multiple transmit antennas to the receiver can be used as an additional information transmitting channel, and the maximum likelihood decoding can be achieved in a simple way by decoupling of the signals conveyed by different methods. The analysis results prove that the capacity behavior of this scheme is better than that of the space-time block coding for the systems with more than two transmit antennas.

In the conventional pilot symbol assisted modulation design, a data block is composed of a pilot set and an information data set. For improving the quality of the channel estimates, some iteration methods use the detected information symbols as the additional pilots. We work on orthogonal frequency division multiplexing (OFDM) system to divide the information data set into several segments and assign them with different data rates for exploiting the potential of the iterative channel estimation. The averaged data rate can be increased by the proposed scheme with the minimum mean-square error channel estimator. The simulation results confirm this approach.

In this paper, we consider the capacity behaviors of MC-CDMA and CP-CDMA systems by the uses of MMSE receivers. The averaged capacities are derived for the two systems, having a finite spreading factor, in Rayleigh fading environment. The closed-form solutions have been obtained, which show that the capacity of the MC-CDMA is slightly larger than that of the CP-CDMA. The theoretical predictions are confirmed by the simulation results.