Abstract-Transmitting large packets over wireless networks helps to reduce header overhead, but may have adverse effect on loss rate due to corruptions in a radio link. Packet loss in lower layers, however, is typically hidden from the upper protocol layers by link or MAC layer protocols. For this reason, errors in the physical layer are observed by the application as higher variance in end-to-end delay rather than increased packet loss rate. In this paper, we study the effect of packet size on loss rate and delay characteristics in a wireless real-time application. We derive analytical model for the dependency between packet length and delay characteristics. We validate our theoretical analysis through experiments in an ad hoc network using WLAN technologies. We show that careful design of packetization schemes in the application layer may significantly improve radio link resource utilization in delay sensitive media streaming under difficult wireless network conditions.

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Significant differences were observed between the two groups of patients with FES and FEM in terms of the hippocampal shape and cortical thickness in the temporal region, highlighting that distinguishable brain structural changes are present early in the course of schizophrenia and mania.

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The psychometric properties of the modified Morisky-Green-Levine Medication Adherence Scale were less than satisfactory. A ceiling effect was observed. The scale may not be an adequate measure to assess medication adherence in patients with Type 2 diabetes in Singapore. Future research could target refining the scale and investigating its use in other patient populations.

In this paper, a new multiple-image encryption and decryption technique that utilizes the compressive sensing (CS) concept along with a double-random phase encryption (DRPE) has been proposed. The space multiplexing method is employed for integrating multiple-image data. The method, which results in a nonlinear encryption system, is able to overcome the vulnerability of classical DRPE. The CS technique and space multiplexing are able to provide additional key space in the proposed method. A numerical experiment of the proposed method is implemented and the results show that the proposed method has good accuracy and is more robust than classical DRPE. The proposed system is also employed against chosen-plaintext attacks and it is found that the inclusion of compressive sensing enhances robustness against the attacks.

The adsorption of chloride on Cu(110) single-crystal surface has been investigated in hydrochloric acid aqueous solution by using in situ scanning tunneling microscopy (STM). A (1 × 1) structure of Cu(110) substrate lattice was visualized at the potentials negative than -450 mV vs SCE, where chloride anions were desorbed. In the potential range from -400 mV to -150 mV vs SCE, two main complex adlayers with 3-fold and 4-fold periodicity along [11 h0] direction of the substrate were observed. These structures with long-range periodicity are attributed to ordered chloride adlayers on unreconstructed Cu( 110)-(1 × 1) structure. The different corrugation heights and periodic modulations along [11 h0] direction observed in STM images indicate that chloride anions are located at nonequivalent binding sites. The average measured lattice constants for the two adlayers have the same size as the substrate lattice along [001] direction and have 4 and 5 times the lattice spacing of the underlying copper substrate along [11 h0] direction. Models are proposed to interpret these two structures to (4 × 1) and (5 × 1) chloride adlayers containing three and four chloride anions, respectively.

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