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This study developed a method to determine the optimum supply of shared cars according to personal travel behaviors in the condition of minimum energy consumption. We applied the method in Southern Higher Education Zone (SHEZ) of Ningbo based on the survey data of personal travel behaviors in the region. Solutions in the case of minimum energy consumption encourage more shared-car trips, less private-car trips, and mass-transit trips. Total of 111 kJ of energy could be saved by each student from the actual case to minimum energy case. In SHEZ, 76 shared cars are recommended to provide an optimal supply of shared cars compared to 87 shared cars in reality. According to the findings, two policy implications are put forward from the aspects of supply and demand. First, to make an efficient supply, companies should focus on the distribution of shared cars according to the temporal and spatial distribution of usage, rather than only number of vehicles. Meanwhile, it is important to increase the usage of shared cars through policies, such as campaigns that raise residents' awareness of car sharing as a green, flexible, and all-distance travel option for both workdays and holidays, and countermeasures that promote the usage of shared cars by key groups such as non-car owners. This study not only provides a method to estimate the optimum supply from viewpoint of minimum energy consumption, but also provide policy implications to guide the behaviors of both companies and users to improve the efficient usage of shared cars in Ningbo real case. [ABSTRACT FROM AUTHOR]

The Caofeidian Reclamation Project has been the biggest reclamation project in China so far, in which 310km2 sea areas were reclaimed along the coast of Hebei Province, and it also bring about many problems and defects for large reclaiming area. The study focuses on the influences of the engineering exerted on evolution of the Laolonggou Lagoon with the methods of topographical measurement and surface sediment analysis. The results demonstrate that the topographical changes in the Laolonggou Lagoon had been controlled obviously by the engineering at three stages. Besides, blocking and reopening of the shoal tidal channel also affected the geological environment of the lagoon area. In the aspect of topographical change, the Laolonggou Inlet first experienced deposition after the shoal tidal channel was blocked, followed by short-time eroding for quarrying and cofferdam construction in the east, then depositing slowly after the reclaiming activity ceased, and finally eroding after the shoal tidal channel was reopened. The project, particularly cofferdam construction led to the movement of the Laolonggou Inlet axis from west to east for 50–100m. In the aspect of sediment variation, the reclamation project and hydrodynamic change resulted in the variation in compositions and distribution pattern. The western lagoon area has become land mainly constituted by silt, while the sediments in the eastern area have turned finer in size. After the shoal tidal channel was reopened, the current velocity in the Laolonggou Inlet has been enhanced, making the sediments at the bottom become coarser. The sediments around the Caofeidian foreland went through a process of changing in grain size from fine to coarse and back to fine again, and the sediments are mainly constituted by silt at present. [ABSTRACT FROM AUTHOR]

Sulfur/multi-walled carbon nanotubes (MWCNTs) composites have been successfully prepared by an in situ growth strategy as a cathode material for lithium/sulfur battery. The microstructure and morphology of the sulfur/MWCNTs composites are characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). From the results, it is found that the nano-sulfur (shell) grows around the MWCNTs (core) and is well-dispersed over the whole surface of the MWCNTs. Tested by coin type cells, the composite materials exhibited the sulfur utilization approaching to 78% for the first cycle, the capacity retention closing to 84% after 100 cycles at various rates. The excellent electrochemical performance could be attributed to the nano-size sulfur and the homogeneous distribution of sulfur on MWCNTs matrix, resulting from this novel in situ growth method, which not only enhances the reactive activity of sulfur during charge-discharge processes but also provides stable electrical and ionic transfer channels. [ABSTRACT FROM AUTHOR]

In this paper, a fast ESPRIT algorithm is presented for two-dimensional (2D) direction-of-arrival (DOA) estimation of coherent signals with a linear acoustic vector-sensor array. Conventional space smoothing ESPRIT (SS-ESPRIT) algorithm for acoustic vector-sensor array has two obvious weak points: (1) eigenvalue decomposition (EVD) of high-order covariance matrix; (2) frequently occurring parameters mismatch which leads to failed 2D DOA estimation. The proposed algorithm can remove the two shortcomings. Firstly, we use two selection matrices to separate received data and form a low-order cross-covariance matrix. Then, ESPRIT algorithm is used to estimate the elevation angles of incident signals. At last, using the estimated elevation angles, a modified array manifold matching method is used to estimate the azimuth angles of coherent signals. During the estimation process of azimuth angles, the proposed method is not required to perform any peak search or EVD. Moreover, azimuth angles are automatically matched with the estimated elevation angles. Compared with the conventional SS-ESPRIT algorithm, the proposed algorithm has lower complexity. However, the estimation accuracy of proposed method almost is the same as the conventional SS-ESPRIT algorithm and far better than PM algorithm. Numerical simulations are presented to demonstrate the performance of the proposed algorithm. [ABSTRACT FROM AUTHOR]

The economic benefits of insect-resistant genetically modified (GM) crops have been well documented, but the impact of such crops and the consequent reduction in pesticide use on farmers' health remains largely unknown. Through the analysis of the data collected from the physical examination from farmers in China, we show that GM rice significantly reduces pesticide use and the resultant not only visible but also invisible adverse effects on farmers' neurological, hematological, and electrolyte system. Hence, the commercialization of GM rice is expected to improve the health of farmers in developing countries, where pesticide application is necessary to mitigate crop loss. [ABSTRACT FROM AUTHOR]

Nickel oxide/multi-walled carbon nanotube (NiO/MWCNT) composites were fabricated via a vacuum solution infiltration method combined with a calcination treatment. The crystalline structure and morphology were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) with selected area electron diffraction (SAED). The specific surface area, pore size, and pore volume were obtained by Brunauer-Emmett-Teller (BET). The as-prepared NiO/MWCNT composites deliver an initial discharge capacity of 1,015 mAh g with 86 % capacity retention (873 mAh g) after 50 cycles at a current rate of 0.1 C. The enhanced electrochemical performance is ascribed to the nanosized NiO and MWCNTs which can act as buffering matrix to relax the volume expansion and electron transfer conductor in the composites. [ABSTRACT FROM AUTHOR]

In this work, spinel structure MgFeO nano-crystals were synthesized by sol-gel auto-combustion method. Morphology and structure of the synthesized MgFeO material is characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). And its electrochemical properties were investigated at different active material ratio. Galvanostatic charge/discharge and cyclic voltammograms (CVs) measurements show that the electrode with a ratio of 40:40:20, which is the ratio of active material: super-P carbon (SP): polyvinylidene fluoride (PVDF), presents relatively superior performance with the initial discharge capacity of 1,123 mAh g and charge/discharge efficiency of 96.7 %. And after 50 cycles, it still maintains at 635 mAh g, which is nearly double that of the other two electrodes with active material ratio of 60:25:15 and 80:15:5. Electrochemical impedance spectra testing shows that the charge transfer resistance (Rct) decreases along with the increasing amount of SP, which is benefit for reducing the polarization and improving the cycling stability of the electrode to a certain extent. [ABSTRACT FROM AUTHOR]