Summary When agricultural land is no longer used for cultivation and allowed to revert to natural vegetation or replanted to perennial vegetation, soil organic carbon can accumulate. This accumulation process essentially reverses some of the effects responsible for soil organic carbon losses from when the land was converted from perennial vegetation. We discuss the essential elements of what is known about soil organic matter dynamics that may result in enhanced soil carbon sequestration with changes in land‐use and soil management. We review literature that reports changes in soil organic carbon after changes in land‐use that favour carbon accumulation. This data summary provides a guide to approximate rates of SOC sequestration that are possible with management, and indicates the relative importance of some factors that influence the rates of organic carbon sequestration in soil. There is a large variation in the length of time for and the rate at which carbon may accumulate in soil, related to the productivity of the recovering vegetation, physical and biological conditions in the soil, and the past history of soil organic carbon inputs and physical disturbance. Maximum rates of C accumulation during the early aggrading stage of perennial vegetation growth, while substantial, are usually much less than 100 g C m−2 y−1. Average rates of accumulation are similar for forest or grassland establishment: 33.8 g C m−2 y−1 and 33.2 g C m−2 y−1, respectively. These observed rates of soil organic C accumulation, when combined with the small amount of land area involved, are insufficient to account for a significant fraction of the missing C in the global carbon cycle as accumulating in the soils of formerly agricultural land.

This article presents an unequal Gysel power divider (UGPD) based on circuit transformation, which is converted from a Pto a T-type circuit. The P-type circuit of a conventional unequal Gysel divider consists of two different value resistors and its connection transmission line. In the proposed T-type circuit, the dummy transmission line and the other transmission line with shunt resistor at center position is connected in parallel. Theoretical analysis was performed to derive the design equations for the proposed circuit conversion. For the validation of the circuit transformation, the UGPD using a T-type circuit at the center frequency of 2 GHz was fabricated and measured. The measured characteristics agreed well with the simulation results. V C 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1529-1531, 2015; View this article online at wileyonlinelibrary.com.ABSTRACT: An electromagnetic band gap resonator antenna (ERA) with an extremely small footprint is presented. The proposed ERA has a peak measured gain of 15.6 dBi and an excellent measured 3dB gainbandwidth of 27%. The four-layer composite superstructure used in this ERA takes the shape of a circular disc with the ground plane radius equal to that of the superstructure. Its footprint area is only 1.7k 0 2 at the lowest operating frequency. The average measured aperture efficiency of this ERA is nearly 90%. The side lobe levels are well below 212 dB over most of the operating bandwidth and the cross polarization levels are below 217 dB. V C 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1531-1535, 2015; View this article online at wileyonlinelibrary.com.

Developing a means by which to compete with commonly used Si‐based memory devices represents an important challenge for the realization of future three‐dimensionally stacked crossbar‐array memory devices with multifunctionality. Therefore, oxide‐based resistance switching memory (ReRAM), with its associated phenomena of oxygen ion drifts under a bias, is becoming increasingly important for use in nanoscalable crossbar arrays with an ideal memory cell size due to its simple metal–insulator–metal structure and low switching current of 10–100 μA. However, in a crossbar array geometry, one single memory element defined by the cross‐point of word and bit lines is highly susceptible to unintended leakage current due to parasitic paths around neighboring cells when no selective devices such as diodes or transistors are used. Therefore, the effective complementary resistive switching (CRS) features in all Ti‐oxide‐based triple layered homo Pt/TiOx/TiOy/TiOx/Pt and hetero Pt/TiOx/TiON/TiOx/Pt geometries as alternative resistive switching matrices are reported. The possible resistive switching nature of the novel triple matrices is also discussed together with their electrical and structural properties. The ability to eliminate both an external resistor for efficient CRS operation and a metallic Pt middle electrode for further cost‐effective scalability will accelerate progress toward the realization of cross‐bar ReRAM in this framework.

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A dual-band on-body repeater antenna for in-on-on wireless body area network applications is proposed. The proposed antenna has a maximum radiation normal to the human-body surface for communication with implanted devices in the 5.8 GHz industrial, scientific, and medical (ISM) band. In addition, to transmit the biological information received from the implanted devices to other on-body devices, the proposed antenna was designed to have a monopole-like radiation pattern along the surface of the human body for communication in the 2.45 GHz ISM band. The antenna was fabricated, and its performance was measured by attaching it to a human-equivalent semisolid phantom. In addition, the human-body effect was studied to ensure antenna performance under an actual situation.