The classical linear multi-factor stock selection model is widely used for long-term price trend prediction. However, the market chaotic, complex, and dynamic, which reasons assumption may be unreasonable, it more meaningful to construct a better-integrated based on different feature nonlinear prediction methods. In this paper, features are selected by various algorithms, parameters of machine learning-based models set through time-sliding window cross-validation 8-year data Chinese A-share...

Narrowband Internet of Things (NB-IoT) is a new technology being implemented into the Long-Term Evolution (LTE) standards to support machine-to-machine communications. Applications IoT are expected rapidly increase and expand many sectors. Increased number devices trying access medium with typically small data packets will overwhelm network. Cognitive radios coupled random strategies can help alleviate excessive collisions in network by attempts. On other hand, most do not have hardware...

In this paper, we propose a maximum likelihood method for jointly estimating carrier frequency offset (CFO) and sampling (SFO) in receivers orthogonal division multiplexing signals. The proposed estimator exploits the fact that single source (such as crystal oscillator or voltage controlled oscillator) is typically used modern wireless to provide reference both clock radio synthesizers. CFO capable of large estimation range (i.e., more than half intercarrier spacing) without extending length...

One of the prerequisites for normal operation a small and medium-scale wireless sensor network is ability to diagnose node failures. Considering characteristics scale, low-density distribution, stable topology fact that each can be monitored, method detecting identifying failure based on Principal Component Analysis (PCA) wavelet decomposition proposed in order improve stability reliability. The principal component analysis model established utilizing historical data collected by nodes are...

The increasing guidance requirement in choosing mutual funds contribute to the development of an abundant literature on approaches ranking performance. However, all commonly used single index and multi-indexes methodologies have their own drawbacks are fact not suitable for a reasonable practical comprehensive sometimes. More specifically, measures incomprehensive, controversial, or even ineffective sometimes, while mostly methods do make full use evaluation information usually indirect...

The main advantages of random access networks are the ability to work with little or no infrastructure and independent transmission users. Thus, users themselves in a network decide when channel. Design cognitive radio (CR) necessitates integrating unique functions such as spectrum sensing, policy configuration databases, self-configuration, etc. Spectrum sensing is especially crucial terms determining channel availability characterization. traditional approach assumes centralized through...

Future wireless devices have to support many applications (e.g., remote robotics, automation, and mobile gaming) with extremely low latency reliability requirements over connections. Optimizing transceivers while switching between connections different circuit characteristics requires addressing hardware impairments that been overlooked previously. For instance, transmission reception radio functions facilitate time-division duplexing can change the load on power supply. As supply voltage...

Abstract Qin-1 is a Z-pinch pulse power generator. Due to the diagnostic requirements of its wire array Z-pinch, two-axis temporal-spatial resolution XUV/SR imaging system has been developed. The composed filters, two gated pinhole cameras, and synchronized electric control system. Each camera consists array, four-frame microchannel plate image intensifier CMOS camera. whole can synchronously diagnose plasma from directions with time 3 ns. spatial approximately 51 μm when diameter 20...

In the scenario where Unmanned Aerial Vehicle(UAVs) are served as mobile base-stations to provide coverage communication for ground users, deployment of UAVs base stations has always been a key challenge. Due limited power UAV, when deploying it is necessary consider cover many users possible with transmission and shortest time while meeting requirements users' Quality Service(QoS). this paper, UAV station modeled three-dimensional(3D) problem. For ease calculation, position decoupled into...

We introduce the fading memory recursive least squares (FM-RLS) and rolling window ordinary (RW-OLS) methods to predict CSI 300 intraday index return in Chinese stock market. Empirical results show that performances are better than of same sign method. The additional profit is mainly from two conflict signals, with one amplitude far greater other.

The cognitive radios (CR) utilize the spectrum resource without interfering primary users (PU). Spectrum sensing, by which CR detects radio environment, is a critical technique in radios. Various collaborative sensing schemes are proposed to either improve sensitivity or reduce duration. However, most of previous studies have not investigated impact on network level. Therefore, this paper we investigate level performance under ALOHA protocol while using autonomous scheme where independent...

BP neural network is a multilayer feed-forward network, it achieved from input to output arbitrary nonlinear mapping, and weights are adjusted by using the back propagation learning algorithm. Intrusion detection systems ability of extract data profile, also can use has self-learning parallel processing ability, through construction intelligent classifier identify abnormal, so as achieve purpose detecting intrusion behavior. The paper proposes development system based on improved network....

Orthogonal frequency division multiplexing (OFDM) has been proven to be very sensitive carrier drifts due fact that both offset (CFO) and sampling (SFO) destroy the orthogonality cross multiple subcarriers. The clock local oscillator, from which is derived, sharing a common reference becoming configuration extensively used in wireless transceivers. In this paper, we propose maximum likelihood (ML) estimation scheme with assumption. We further two CFO estimators low computational complexity -...

With the enhanced awareness of energy conservation and eye health, more concerns attentions are focused on teaching building lighting control technologies related products. In order that management can be facilitated effects conditions improved, automatic system for is designed by adopting Dimmable electronic ballasts wireless sensor network. To achieve light switch regulation intensity, infrared chosen to detect human body illumination used illuminance values. System operation shows stable,...

This paper studies the relay selection in wireless cooperative communication systems. Since high mobility of Unmanned Aerial Vehicles (UAVs) will lead to change link state, a algorithm based on position prediction is proposed this better study problem. First, Unscented Kalman Filter (UKF) used predict real-time location information each UAV, and information, it determined whether current UAV node needs be replaced. The predicted by UKF algorithm, which basis for determining Then, outage...

Main function of the intelligent home control system in internet things is including family equipment automatic and security. The applied technology STC89C52 chip GSM module TC35 modem are as core, temperature, humidity sensor for environmental information acquisition source, to create a smart Home Furnishing system. content experimental prototype includes design hardware software debugging controlling writing debugging. results show that, circuit can finish test basic functions.

Switching operation happens extensively in nowadays wireless devices between various functional modules. The transient responses during the hardware switching are non-ideal due to behavior of components. may cause distortion on signals and degenerate system performance before effect is settling down. We explore advanced solutions compensate impairments rather than, as conventional treatment, inserting guard intervals. In this paper, we present carrier frequency offset (CFO) observed testbeds...

The technical features of RFID and sensor network, inherits the radio frequency signal characteristic automatic target recognition, at same time, implementation a wireless network active perception communication function. This paper analyzed integration ZigBee technology; each node can be coordinated in real-time monitoring, sensing collecting regional distribution variety environmental or monitoring information. puts forward development based on technology. Wireless is Zigbee GSM used for...

Covariance matrix estimation plays a significant role in both the theory and practice of portfolio analysis risk management. This paper deals with available data prior to developing factor model enhance covariance estimation. Our work has two main outcomes. First, for general linear unknown parameters, class best empirical Bayes estimators is established through kinds architectures improve accuracy by utilizing additional prior. The theoretical results indicate key points: proposed are...

Green building materials in the industry is also known as natural materials, construction and environmental health materials. development utilization are of following types, one to save resources, such fly ash mixture reduce consumption resources. Wireless sensor network Zigbee used for data communication based on networks. The paper proposes research green engineering system wireless technology. Experimental results show that proposed technology has high efficiency.

The evaluation of covariance matrix estimators is very important for portfolio analysis and risk management. Monte Carlo synthetic sample based performance method proposed by this article can avoid the main shortcomings statistical economic methods which are widely used in existing literature. does not need true to introduce out-of-sample portfolios. It an intuitive, effective robust measure both simulation empirical analysis.