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High-resolution images of human brain are critical for monitoring the neurological conditions in a portable and safe manner. Sound speed mapping of brain tissues provides unique information for such a purpose. In addition, it is particularly important for building digital human acoustic models, which form a reference for future ultrasound research. Conventional ultrasound modalities can hardly image the human brain at high spatial resolution inside the skull due to the strong impedance contrast between hard tissue and soft tissue. We carry out numerical experiments to demonstrate that the time-domain waveform inversion technique, originating from the geophysics community, is promising to deliver quantitative images of human brains within the skull at a sub-millimeter level by using ultra-sound signals. The successful implementation of such an approach to brain imaging requires the following items: signals of sub-megahertz frequencies transmitting across the inside of skull, an accurate numerical wave equation solver simulating the wave propagation, and well-designed inversion schemes to reconstruct the physical parameters of targeted model based on the optimization theory. Here we propose an innovative modality of multiscale deconvolutional waveform inversion that improves ultrasound imaging resolution, by evaluating the similarity between synthetic data and observed data through using limited length Wiener filter. We implement the proposed approach to iteratively update the parametric models of the human brain. The quantitative imaging method paves the way for building the accurate acoustic brain model to diagnose associated diseases, in a potentially more portable, more dynamic and safer way than magnetic resonance imaging and x-ray computed tomography.

Aiming at mode selection in D2D communication, a mode selection strategy based on social-aware was proposed. In addition to physical connection status, users’ social relationships also served as an observation element. Through relationship between users, the closeness of user relationship can be judged, and then through users’ reference, the similarity between users can be obtained. In this way, by combining physical connection with social relationships, users’ aggregate utility was acquired. According to the physical connection quality and the social relationship strength, taking maximizing users’ aggregate utility as the goal, a random algorithm was designed to match users. Simulation results show that mode selection based on social perception can effectively improve users’ aggregate utility.

A Dante network card and development template developed by Audinate were used as a platform for realizing an Ethernet synchronous audio playback system. A personal computer (PC) was connected to each Dante device through a switch hub and Ethernet cable PC to transmit sound before TAS3204EVM was applied in digital signal processing and EQ adjustment for application in a live music concert. The expensive wire and cable currently used in live music concerts can be replaced with an Ethernet cable, substantially reducing costs. To ensure that the Dante devices deliver sound simultaneously, an artificial delay was introduced to enable devices closer to the sound source to delay the playback time while devices farther from the sound source play back sound with the other devices. This study examined how the IEEE 1588 Precision Time Protocol can be used for clock correction to synchronize the sound of all devices. Zero Configuration Networking (ZCN) was used to enable the devices to obtain an Internet Protocol address, and the Multicast Domain Name System was employed to obtain the device names, thus ensuring that User Datagram Protocol control instructions can be correctly delivered to control interdevice channel connections.

In a D2D (Device-to-Device) communication system, mode selection is studied by taking SINR of D2D users as the baseline. Firstly, in this paper, mode selection is transformed into an optimization problem taking maximization of system throughput as an object. A heuristic algorithm is proposed in order to reduce computation complexity and the problem is decomposed into two subproblems of mode selection and resource allocation. Assuming that cell channel state information is available, the conditions of shared mode, dedicated mode and cellular mode used by D2D users are obtained respectively and a resource allocation strategy is designed for dedicated mode. Simulation result shows that the algorithm can improve transmission rate of D2D users effectively.

In recent years, the consumption demand of major agricultural products in Guangdong Province presents new characteristics, main consumption of agricultural products is the trend of different, rice and vegetable consumption to smooth fluctuations, edible oil, meat, fruits and aquatic products consumption showed varying degrees of growth. From the perspective of consumption structure, consumption structure of urban and rural agricultural products exist great differences, such as rice, vegetables urban per capita consumption of stabilization, the consumption of rural residents began to decline. The change of consumption structure led to the main agricultural products in Guangdong Province Import and export situation change, the import and export of the main agricultural products in Guangdong was deficit, most of the wheat and other grain need from other provinces transferred. By using GM (1, 1) model on the consumption of main agricultural products in Guangdong make demand forecasting, has found that consumer demand for the next ten years of rice, vegetables, edible oil, meat, fruits and aquatic products showed a trend of increase in the flat, and according to the forecast results to make the corresponding policy recommendations.

Aim: Use the National Health Insurance Research Database of Taiwan to determine whether patients with posttraumatic epilepsy (PTE) have an increased risk of mortality. Methods: Patients &ge, 20 years old ever admitted because of head injury (per International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes 850&ndash, 854 and 959.01) during 2000&ndash, 2012 were enrolled into a traumatic brain injury (TBI) cohort. The TBI cohort was divided into with PTE (ICD-9-CM code 345) and posttraumatic nonepilepsy (PTN) cohorts. We compared the PTE and PTN cohorts in terms of age, sex, and comorbidities. We calculated adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) of all-cause mortality risk in these cohorts. Results: Patients with PTE had a higher incidence rate (IR) of mortality than did patients with TBI alone (IR per 1000 person-years: 71.8 vs. 27.6), with an aHR 2.31 (95% CI = 1.96&ndash, 2.73). Patients with PTE aged 20&ndash, 49, 50&ndash, 64, and &ge, 65 years had, respectively, 2.78, 4.14, and 2.48 times the mortality risk of the PTN cohort. Patients with any comorbidity and PTE had 2.71 times the mortality risk as patients in the PTN cohort. Furthermore, patients with PTE had 28.2 increased hospital days and 7.85 times as frequent medical visits per year compared with the PTN cohort. Conclusion: Taiwanese patients with PTE had approximately 2 times the mortality risk and an increased medical burden compared to patients with TBI only. Our findings provide crucial information for clinicians and the government to improve TBI outcomes.

Purpose of this research wants to use a device, called Dante board, the board enabled AD converter. It digitalizes audio and transmits the audio using TCP/IP technology through cat5 cable to replace the expensive analog cable used in the past. Still, there are some problems needed to be overcome. First of all, during the analog-to-digital process, distorted audio issues are often encountered due to inconsistency of the encoder during digital sampling. In order to compensate the distortion during the conversion, frequency needs to be filtered out to compensate or attenuate. Secondly, due to delay in Internet transmission, the audio outputs by each device may not be synchronized. Therefore, each device needs to have its own clock to overcome the delay and reach the synchronized effect through clock synchronization. Also, the IEEE1588 precision time protocol (PTP) is used in clock synchronization to synchronize the audio in each device.

Atmospheric duct is an anomalous structure with a high probability in the sea. Rough sea surface exists as an air-sea boundary, which can enable electromagnetic wave propagation more complex in atmospheric duct due to scattering. By the Fourier split-step algorithm of the standard parabolic equation and the impedance boundary conditions, the transmission loss in atmospheric duct for different kind of rough sea is analyzed. Numerical results show that the rough sea surface in atmospheric duct can increase significantly the loss of electromagnetic wave, and some blind area at the horizontal distance will disappear. But at the same time the electromagnetic energy loss caused by rough sea surface increases will also make the over-the-horizon detection more difficult.

A stable form-phase change materials (PCM), based on capric-lauric acid eutectic served as the absorption material and the support of nano-silica material to prepare by sol-gel method. The best ratio capric-lauric acid eutectic combination is determined for 60 wt. %. Capillarity because of the influence of the hydrogen bonding, fatty acid and eutectic can be fixed in the three dimensional network structure of the construction of the silicon atom bonds and O still so solid sample melting point composite heating more fatty acid eutectic. Form and chemical properties of the composite phase change the transmission electron microscope, semi and Fourier transform infrared method.- Differential scanning calorimetric hot method is used for measuring phase transition temperature and phase change of latent heat composite, value 19.57 and 71.28 J/g , respectively. At the same time, service performance and other composite material thermal stability and thermal conductivity coefficient test using thermo gravimetric analysis and transient hotline method, respectively.

Based on strong and weak forms of elastic wave equations, a Chebyshev spectral element method (SEM) using the Galerkin variational principle is developed by discretizing the wave equation in the spatial and time domains and introducing the preconditioned conjugate gradient (PCG)-element by element (EBE) method in the spatial domain and the staggered predictor/corrector method in the time domain. The accuracy of our proposed method is verified by comparing it with a finite-difference method (FDM) for a homogeneous solid medium and a double layered solid medium with an inclined interface. The modeling results using the two methods are in good agreement with each other. Meanwhile, to show the algorithm capability, the suggested method is used to simulate the wave propagation in a layered medium with a topographic traction free surface. By introducing the EBE algorithm with an optimized tensor product technique, the proposed SEM is especially suitable for numerical simulation of wave propagations in complex models with irregularly free surfaces at a fast convergence rate, while keeping the advantage of the finite element method.

We present a bulk micromachined in-plane capacitive accelerometer fabricated with an improved process flow, by etching only one-fifth of the wafer thickness at the back of the silicon while forming the bar-structure electrode for the sensing capacitor. The improved flow greatly lowers the footing effect during deep reactive ion etching (DRIE), and increases the proof mass by 54% compared to the traditional way, resulting in both improved device quality and a higher yield rate. Acceleration in the X direction is sensed capacitively by varying the overlapped area of a differential capacitor pair, which eliminates the nonlinear behavior by fixing the parallel-plate gap. The damping coefficient of the sensing motion is low due to the slide-film damping. A large proof mass is made using DRIE, which also ensures that dimensions of the spring beams in the Y and Z directions can be made large to lower cross axis coupling and increase the pull-in voltage. The theoretical Brownian noise floor is 0.47 µg/Hz1/2 at room temperature and atmospheric pressure. The tested frequency response of a prototype complies with the low damping design scheme. Output data for input acceleration from −1 g to 1 g are recorded by a digital multimeter and show very good linearity. The tested random bias of the prototype is 130 µg at an averaging time of around 6 s.

Guiding young learners' attention improves their self-directed learning skills, and that attention can be analyzed via the learners' eye movements. Thus, we propose a self-directed learning system integrating eye trackers with a web based interface to provide an attention guiding function that aims at notifying the learners about the ignored or the skipped parts from the learning material as well as providing hints about the confusing sections. We aim at implementing a cost-effective system that can be used by learners not only at school, but also at home. In conclusion, we believe that the proposed system can be considered as effective tool to enhance the learners' self-directed learning skills.

Many studies were done on design algorithms to completely cover an area. We can call the issue as a complete coverage problem. Although there were many researches about proposing a partial coverage issue; almost all of the studies only focus on lengthening the lifespan of wireless sensor networks (WSNs) but ignore the truth that a wireless sensor network will inevitably lose its coverage because of exhausted energy during the operating time. Lifespan refers to wireless sensor network offering its service to meet the required coverage ratio. In this work, we propose a topology control algorithm for cluster-based wireless sensor networks to keep predefined Quality of Service (QoS) of coverage as long as the sensor nodes can stand. The algorithm forms a multi-hop cluster network with a required connectivity by using a novel cluster head competition scheme and proper transmission of power settings. It can organize sensor nodes into clusters actively to achieve required coverage ratio as long as possible. The algorithm is suitable for practical applications of large-scale or high-density wireless sensor networks due to its distributed processing and scalable cluster topology

According to the data characteristics of pigs, eggs and early indica rice, rice varieties broken down into the season, trend, cycle, and the random component, with the method of X-12, H-P Adjustments and estimate. It turns out that: random shocks in most years less the impact of pigs、eggs and early indica rice prices, deterministic trend is dominated by abnormal price fluctuations less. In addition, the pig、egg and early indica rice price since 2000 experienced a total of three complete cycles, average cycle length of 39 months.

As a wireless sensor network consists of a large number of randomly distributed nodes, one of the most challenging issues is to guarantee the required coverage and connectivity within the entire WSN’s life cycle. This paper proposes a topology control algorithm which is improved from a previous study abbreviated as ARC for large-scale WSNs with randomly deployed nodes. According to the preliminary simulation results, the improvement has been proved that the proposed method can maintain the quality of service by coverage intensity much longer than original design.

In this paper, we demonstrate that the simple maximum carrier to interference ratio (CA) scheduling can both enhance system throughput and maintain fairness performances for an orthogonal frequency division multiple access (OFDMA) system. The maximum C/I scheduling has long been recognized as an effective method to enhance throughput, but it is viewed as an unfair scheduling policy in the single carrier time division multiple access (TDMA) or code division multiple access (CDMA) system. We reassess the fairness performance of the maximum C/I scheduling in the multi-carrier OFDMA system. Through analysis and simulations, our results show that the fairness of the maximum C/I scheduling in OFDMA systems is comparable to that of the proportional fair scheduling scheme.