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Mobile crowdsensing is a novel sensing paradigm enabled by the proliferation of mobile devices. Since crowdsensing applications are driven by sufficient users, advanced incentive mechanisms have been designed to enhance users' willingness to participate in sensing tasks. However, incentive mechanisms only provide adequate sensing opportunities on the condition that the available user base is large. If existing users are fewer than the required number of participants, incentive mechanisms will lose efficacy. This article proposes a hybrid framework called HySense to compensate for inadequate sensing opportunities solely provided by incentive mechanisms. Within each sensing cycle, HySense combines mobile devices with static sensor nodes to generate uniformly distributed space-time data under the constraint of field coverage. To balance sensing opportunities among different geographic regions, redundant users are efficiently migrated from densely populated areas to sparsely populated areas. HySense utilizes calibration mode for checking whether the participants' behavior patterns are consistent with the sensing task queue. Therefore, any change caused by unforeseen accidents can be dealt with in advance. [ABSTRACT FROM PUBLISHER]

In this paper, the relationship between the magnetic properties and microstructures of nanocomposite isotropic exchange-coupled systems with the structure of \alpha -Fe crystalline grains embedded in Nd2Fe14B matrices has been estimated by micromagnetic finite-element method. And then, the results have been analyzed by means of the effectiveness of exchange coupling between the magnetically hard Nd2Fe14B and soft \alpha -Fe phase of the exchange-coupled Nd2Fe 14\text{B}/\alpha -Fe magnetic systems. The effectiveness of interphase exchange coupling has been estimated by the volume fractions of exchange coupling area near phase boundaries between \alpha -Fe grains and Nd2Fe14B matrix. The results have shown the micromagnetic mechanism of the advanced magnetic properties of the exchange coupled magnetic systems with the structure of $\alpha $ -Fe grains embedded in Nd2Fe14B matrix. In addition, the optimal magnetic properties can be expected in the case of comparatively the large grain sizes of $\alpha $ -Fe and Nd2Fe14B phase due to the characteristic structure of those magnetic systems. [ABSTRACT FROM AUTHOR]

In this paper, an algorithm for estimating shallow-water depth from hyperspectral data is proposed. This methodology is based on the different responses of shallow-water reflectance on depth and substrate type. Two parameters-similarity coefficient and Pearson correlation coefficient-are introduced to describe the different types of responses, and a linear logarithm ratio model is established. Using Hyperion data over the coastal regions of O'Ahu Island and Saint Thomas Island, the retrieved bathymetry is compared with the airborne LIDAR data. The validation results show that the proposed method has good performance, and the root mean square error is less than 1.5 m over shallow water (shallower than 20 m). [ABSTRACT FROM AUTHOR]

In this paper, we present test structures and measurement techniques that enable the extraction of the significance of the thermal–mechanical stress in 3D-stacked integrated circuit technology. Heaters and integrated diodes have been used to determine the impact of hotspots in 3-D systems. The results obtained showed that in 3-D case, the peak temperature of a hotspot is three times higher compared to a traditional 2-D system. For the characterization of through silicon vias (TSVs)-induced stress and its impact on analog metal-oxide semiconductor (MOS) devices, a 10-bit current steering digital-to-analog converter (DAC) test structure is utilized. The DAC has been optimized to detect ion changes down to 0.5% due to TSV proximity, TSV orientation, thermal hotspots, and wafer thinning or stacking process. The results obtained from stand-alone short-channel MOS devices and the DAC structure clearly indicate the impact of TSV proximity and TSV orientation on the carrier mobility of nearby transistors. [ABSTRACT FROM PUBLISHER]

The main functions of the ITER gas injection system (GIS) are to provide gas fueling for plasma, wall conditioning operation, and neutral beam injectors. The dedicated manifold, which contains independent tubes for \H2/\D2, \H2, \T2, ^4\He/^3\He, \N2/\Ne, Ar, and evacuation, is the key part of the gas injection lines. It shall deliver gases from the tritium plant to various fueling systems. This paper presents an overview of the GIS manifold design, particularly introducing the solution of the penetration structure and the routing of the manifold from the concept design point of view. [ABSTRACT FROM PUBLISHER]

This paper presents an annular-structure lateral-diffused metal–oxide–semiconductor (LDMOS) RF transistor using a 0.5-\mum LDMOS process. This paper also examines the dc, small-signal, and large-signal characteristics of RF LDMOS transistors with different closed structures. In particular, the problem of evaluating the LDMOS aspect ratio for annular structure is addressed. The capacitance characteristics improvement in the LDMOS device design using the annular structure was also investigated. The power gain and efficiency of annular structure give nearly 5% enhancement compared to the traditional structure with 80-\mum gatewidth at 1.9 GHz. Results show that the annular structure appears to be a better layout design for RF LDMOS transistors. [ABSTRACT FROM AUTHOR]

A low-voltage (0.5 V) and low-power (4.535 mW) monolithic biomedical system-on-a-chip (SOC) consisting of a receiver, a transmitter, a microcontrol unit, and an analog-to-digital converter (ADC), implemented in a 0.18- \mu\m CMOS technology for intrabody communication is first reported. The SOC can take command through a human body and activate (or turn on) the ADC and transmitter inside the SOC. Then, a biomedical signal is converted to digital format and transmitted to the RF gateway through a human body. With this transmission methodology and the proposed SOC circuit, it is much more power efficient than wireless communication. Moreover, since no antenna is required, the chip size of the SOC is only 1.5 \mm^2, excluding the test pads. [ABSTRACT FROM AUTHOR]

Dielectric barrier discharge (DBD) is proved to be an effective method for surface treatment of polymers over the past 20 years and is now widely used in the fields of surface modification. In this paper, surface treatment of polyethylene terephthalate (PET) films for improving the hydrophilicity using DBD excited by unipolar nanosecond pulses is presented. Two typical discharges exhibiting homogeneous and filamentary modes are obtained under certain experimental conditions, and then, they are used to modify the surface of PET films. The microstructure and properties of the film surface before and after treatment are characterized with water contact angle measurement, scanning electron microscope, atomic force microscope, and X-ray photoelectron spectroscope. The results show that, with the treatment power density of 192 and 158 mW/cm2 in filamentary and homogeneous modes, respectively, surface morphology and property after treatment are significantly changed, and the physical etching and introduction of oxygen-containing polar functional groups account for the decease of surface contact angle and the increase of surface roughness. Compared with the filamentary DBD treatment, the homogeneous DBD (HDBD) is more effective in surface treatment, such as lower contact angle, higher roughness, and more oxygencontaining function groups after treatment. It is attributed to the fact that the HDBD can achieve a uniform treatment and canmake the physical and chemical interaction much sufficient. [ABSTRACT FROM AUTHOR]

Single fed low profile cavity backed crossed slot antennas for dual frequency dual linear polarization and circular polarization applications are first presented in this paper. By employing the substrate integrated waveguide (SIW) technique in the antenna designs, the low profile backed cavity structure can be realized by using only a single layer of low cost printed circuit board (PCB) substrate. A single grounded coplanar waveguide (GCPW) is employed as the feeding element to excite the TE120 and TE210 modes in the SIW cavity. A crossed slot structure is used as the radiating element in order to radiate the desired dual linearly or circularly polarized wave. From the measurement results, it is seen that these novel antennas retain the advantages of conventional metallic cavity backed antennas, including high gain, high front-toback ratio (FTBR), and low cross polarization level (CPL). Furthermore, the proposed antennas also possess the advantages of low profile, light weight, low fabrication cost, and easy integration with planar circuits. [ABSTRACT FROM AUTHOR]