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This paper proposes a cluster-based distributed medium access control (CDMAC) protocol for multichannel and multihop mobile cognitive radio ad hoc networks (CRAHNs). Secondary users (SUs) of the CRAHNs sense the spectrum to obtain licensed channels opportunistically from primary users (PUs) according to the channel-sensing model. The CRAHN is divided into clusters, with cluster heads determined according to the degree of importance of the nodes. The control and data channels are dynamically selected based on the success probability and stability of the idle PU channels. The traffic adaptively determines the contention window size, and a dynamic contention window mechanism is proposed to reduce the MAC contention delay. Furthermore, this mechanism achieves high throughput for a given contention window size. We also develop a Markov chain model to characterize the performance of our proposed CDMAC protocol for a saturated network. The Markov chain is also characterized by initial-state probabilities and a state-transition probability matrix. We perform extensive simulations to verify that the proposed CDMAC protocol can achieve higher performance in the mobile CRAHNs than other approaches.

Image super-resolution based on learning dictionary has recently attracted enormous interests. The learning-based methods usually train a pair of dictionaries from low-resolution and high-resolution image patches, ignoring the fact that patches have different structures. In this paper, we propose to train a set of novel multi-pairs of dictionaries for different categories of patches which clustered by gaussian mixture model, instead of a global dictionary trained from all patches. The multi-pairs of dictionaries via patch prior guided clustering can express structure information of the image patches well. Extensive experimental results prove it has strong robustness in super resolution. Compared with state-of-the-art SR methods, our method demonstrates more pleasant quality of image edge structures and texture.

In this paper, we propose a distributed multichannel (DMMAC) protocol for multichannel cognitive radio ad hoc networks (CRAHNs). We compare DMMAC with other previous medium access control (MAC) protocols and show that DMMAC provides higher evaluation performance than other protocols.

We report a wafer-scale fabrication process to make large-area slot antenna arrays for studying spontaneous emission enhancement of 2D transition metal dichalcogenide. The experimental results show a 10-fold enhancement of photoluminescence was observed.

To realize the self-learning operation modes recognition of air borne fire control radar, an optimized LSSVM (least squares support vector machine) algorithm based on grid search and K-fold cross validation is proposed. First, extract feature parameters of non-cooperative radar signal and establish library base of radar signal as training sample in LSSVM model. Next, apply grid search method in parameter optimization to realize model adjustment under the circumstance of uncertain sample range. In the sequel, use K-fold cross validation to realize performance evaluation and reduce model error caused by sample randomness, which improves generalization ability. Simulation results show that recognition accuracy of Velocity Search (VS) / Single Target Track (STT) / Range While Search (RWS) / Track While Scan (TWS) modes reaches 97%, proving good recognition performance and practical value of proposed method.

Regarding the deficiencies of clustering algorithm with fast method of searching and finding density peaks which is published in Science in 2014, an automatically and fast finding of clustering centers clustering algorithm is proposed, which applies linear regression and residual analysis and optimizes sample density value. The proposed algorithm improves location stability of clustering centers by measuring point density through sample's nearest neighbors information, and it determines clustering centers fast and automatically by applying linear regression and residual analysis, which reduces the subjectivity of artificial selection. Theoretical analysis and simulation results show that the proposed algorithm can overcome deficiencies of the original algorithm, what's more, the results of clustering effect and calculation time is superior to original algorithm, K-means and DBSCAN.

Path planning for jammers formation is vital to the success rate of penetration operations. Rasterization is applied to construct the discretized operation space. The natural terrains, including random surface model, mountain terrain model are built through the mathematical model. Then, the range threat, mountain threat, radar detection threat and aircraft flight constraint are established as the path threat factors. In view of the defects of the traditional PSO, GA is introduced to improve it through dividing the population into two parts to acquire the comprehensive advantages of the two algorithms. The simulation results indicate that the jamming path with low threat could be acquired through the planning with improved PSO-GA.

A smart grid is a modernized power grid. Many novel technologies have been used to smart grids. One of the technologies is the wireless sensor network. In this study, a novel backbone communication network is proposed, which combines two different wireless technologies (the ZigBee and Wi-Fi protocol), to form a communication network between the transmission towers in a power grid. The gateway in the network consists of an embedded system and an AP with long-range communication capability. The embedded system is used as a computing platform to deal with sensor readings transmitted through the ZigBee protocol and routing data transmitted between towers via long-range Wi-Fi. Finally, the gateways relay the readings to a back-end server in a monitoring center (e.g. substation, ADCC, and CDCC) through the backbone communication network. Furthermore, to manage all the gateways, a routing algorithm for the backbone communication network is designed to ensure the reliability of data transmission in this study. Simulation is done to test the effectiveness and reliability of the routing algorithm. Although other papers have shown architectures and algorithms for smart grid, they are not proper for power grid in Taiwan due to the distribution of transmission lines. This study proposes an embedded system-based backbone communication network for power grid in Taiwan.

With the development of avionics technology, the runway detection technique becomes increasingly important both in military and civil applications. But the existing runway detection methods are mostly intended for satellite images or downward-looking aerial photos and the algorithm complexity is relatively high, which makes it hard to apply them to airborne real-time applications. In this paper, a real-time sensor guided runway detection method is presented. First of all, with the help of sensor data and terrain data from EVS and SVS, a runway template is generated and a search region is therefore determined. Then within the search region, a lines extraction on query image is performed. And finally the matching process is applied to the query image and template to detect the runway area. Experimental results on simulation system and real aerial images show that the proposed approach has a high precision and an 87.7% less time cost than an existing state-of-art matching method.

Among natural disasters, earthquakes are a major factor that damages transmission lines and power towers, but the impacts of earthquakes on transmission towers are less discussed. For many countries, earthquakes often cause power outages. Traditionally, the safety of extra-high voltage (EHV) transmission systems is inspected by the staff of power companies. Due to high labor costs and time consuming patrols, system anomalies are difficult to be identified immediately. Therefore, this study develops a seismic assessment algorithm for electrical grid safety monitoring with the wireless sensing technology to assess seismic hazard for the EHV transmission system. In the monitoring system, the environment sensing data can be transmitted in real-time by a wireless network. And the intensity data can be analyzed by the algorithm immediately after an earthquake occurs. Specifically, peak ground acceleration (PGA) is adopted as the seismic intensity parameter, and effective peak acceleration (EPA) is a reference parameter used to evaluate towers seismic hazard. Based on the simulation and verification results, the accuracy of the proposed seismic intensity algorithm is high, and the calculation speed is fast. Thus, the purpose of early warning can be achieved by using the proposed algorithm.

The efficiency of producing porcine transgenic cloned embryos is still low due to lower developmental competence compared to in vivo-fertilized/cultured embryos. This phenomenon may correlates with poor culture condition. Energy substrate in culture medium play an important role in optimizing culture condition. This study pertain to investigate the effect of replacing pyruvate and lactate with glucose in PZM-3 medium at the rest part culture period on porcine embryonic development after SCNT. Porcine adult fibroblasts cells were transfected with pEGFP-C1 vector. Then transfected cells were used as donor cells for producing re-constructed embryos. Results have shown that supplement of glucose up to 5mM concentration in PZM-3 at the rest part of culture period improved the development of transgenic cloned embryos. Moreover, supplement of glucose(5mM) as energy substrate in PZM-3 at 48h of culture was optimal time. However, with regard to the percentage of EGFP-positive blastocyst, there was no significant difference between treatments. In conclusion, replacing pyruvate and lactate with glucose in PZM-3 medium at the rest part of culture period was beneficial to the development of transgenic cloned embryos and had no effect on transgene expression.

Based on the theoretical analysis of the relationship among financing motivation, financing choice and development strategy orientation of entrepreneurial firms, this paper puts forward a proposition on the impact of financing motivation on development strategy orientation of entrepreneurial firms, which is then tested empirically using survey data from massive Chinese entrepreneurial firms. The research finds that wealth accumulation motivation and self-determination motivation are two main motivations that influence financing choice of entrepreneurial firms. Driven by the two main financing motivations, entrepreneurial firms primarily choose exogenous equity financing and exogenous debt financing. Financing choice affects development strategy orientation of entrepreneurial firms. Exogenous equity financing leads to entrepreneurial firms' active development strategy orientation while exogenous debt financing leads to their steady development strategy orientation.

In this paper, the features of electrical power steering and semi-active suspension systems have been done a more in-depth study. In order to achieve the common objective of improving the ride comfort and handing stability of automobile, an integrated control strategy was proposed to achieve the control of electrical power steering and semi-active suspension systems. In a well on the basis of experimental data, the mathematical model of electrical power steering and semi-active suspension systems were adopted to predict the characteristics of these two systems. In order to achieve the simulation of the integrated control strategy, a PID controller for electrical power steering and an optimum controller for semi-active suspension systems were designed under MATLAB environment, and a vehicle system dynamics model including the electrical power steering and semi-active suspension systems was also established. By automotive ride comfort and handing stability simulation, the integrated control strategy was proved to be effective.