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This study focuses on robust Tomlinson-Harashima precoding transceiver design for multi-cell multiple-input- multiple-output interference channel with statistical channel state information error. The objective is formulated to minimise the maximum per-user mean square error (MSE) with per-transmitter power constraint. Since the problem is not jointly convex, an approximated method is proposed. The authors optimise the receiver matrix to be minimum MSE form as well as derive the optimisation problems of transmitter matrix and feedback matrix to be second-order cone programming, respectively. By use of the results, the three matrices are updated iteratively. The convergence of the proposed method is also proved. Simulation results show that the proposed scheme outperforms the robust linear transceiver in both MSE and bit error ratio. [ABSTRACT FROM AUTHOR]

In conventional schedule-based wireless transmission system, frequent interactions between devices and access networks lead to significant signalling overhead, and thus limit the development of low-latency applications. Contention-based data transmission (CBDT) is widely used as a promising solution to address the above issues. In this study, the authors propose a detection-based retransmission scheme for CBDT to further reduce the delay-outage probability which cannot be avoided due to collision. In this scheme, each device simultaneously monitors the occupied resource blocks during data transmission. When a collision event is detected, the retransmission for this packet is determined without waiting for the acknowledgment message from the receiver. The reliability performance is significantly improved for low-latency applications, since the possible retransmission times for each packet is increased within the limited transmission period. In addition, the impacts of imperfect detection on extra transmission load and packet loss are analysed in detail. The simulation and analytical results demonstrate that the detection-based scheme significantly improves the reliability of CBDT. [ABSTRACT FROM AUTHOR]

The traditional method for visualization of 3D city models based on a "Layer-Object" does not consider the granularity differences in different data type and in different levels of detail, which results in the low transmission efficiency in the network environment and does not satisfy the need for smooth visualization with multi-user concurrent accesses. This paper analyzes the characteristics of an user experience including roaming over a wide range and focusing on small range, and proposes a method of using an index metadata to coordinate the organization and scheduling of model objects, which delivers instant responses to user requests, and at the same time, by decomposing model objects, decreases invalid data transmission. This paper describes the design of unified object ID structure to implicitly store the relationships of LoD models and decomposed objects to support distributed management. Finally, the validity and feasibility of this method are demonstrated through experiments on the platform of a distributed database MongoDB. [ABSTRACT FROM AUTHOR]

While the NAND flash memory is widely used as the storage medium in modern sensor systems, the aggressive shrinking of process geometry and an increase in the number of bits stored in each memory cell will inevitably degrade the reliability of NAND flash memory. In particular, it's critical to enhance metadata reliability, which occupies only a small portion of the storage space, but maintains the critical information of the file system and the address translations of the storage system. Metadata damage will cause the system to crash or a large amount of data to be lost. This paper presents Asymmetric Programming, a highly reliable metadata allocation strategy for MLC NAND flash memory storage systems. Our technique exploits for the first time the property of the multi-page architecture of MLC NAND flash memory to improve the reliability of metadata. The basic idea is to keep metadata in most significant bit (MSB) pages which are more reliable than least significant bit (LSB) pages. Thus, we can achieve relatively low bit error rates for metadata. Based on this idea, we propose two strategies to optimize address mapping and garbage collection. We have implemented Asymmetric Programming on a real hardware platform. The experimental results show that Asymmetric Programming can achieve a reduction in the number of page errors of up to 99.05% with the baseline error correction scheme. [ABSTRACT FROM AUTHOR]

The creation and widespread adoption of the OpenURL standard has improved the visibility, and therefore the usage, of libraries' online holdings, although there are some times when OpenURLs fail to resolve. To better understand why problems occur and encourage network-level solutions, librarians at Cornell University have begun working on a study of OpenURL metadata quality. Their goal is to create a systematic approach to assessing and validating metadata quality so that libraries and content providers may collaborate on solutions for metadata problems. One member of this project team, Glen Wiley, shared details about the types of problems this approach seeks to remedy and the status of the project. [ABSTRACT FROM AUTHOR]

The article presents information on metadata standards and includes a collection of web addresses for essential resources in this area to help library catalogers. It is stated that metadata standards are an emerging field, where frequent change and development are an ongoing process. Substitute methods for describing digital objects and storing/transmitting data about these objects are useful to explore for a variety of reasons. The list of web addresses includes Machine Readable Cataloging (MARC) Standards, lcweb.loc.gov/marc, MARC21 DTDs for SGML and XML, lcweb.loc.gov/marc, Metadata Encoding and Transmission Standard (METS) http://lcweb.loc.gov/mets.